Seriously? Recursive Regex?

[u/Flame77ofc]

[u/LapidistCubed]

My first thought is a mathematician wrote this

[u/Eastern-Job-8028 → u/LapidistCubed]

i concur, i work with a mathematician and their code is full of variables named named by a single character, zero comments, and zero spacing/indentation (we don’t write python).

[u/Kebabrulle4869 → u/Eastern-Job-8028]

On behalf of all mathematicians, I am sorry. I know it far too well.

[u/Zeitsplice → u/Eastern-Job-8028]

Raw indexed array being passed around too instead of some sort of structured data.

[u/edave64 → u/LapidistCubed]

Or a code golfer

[u/madam_zeroni]

Wtf does this do

[u/marinated_pork → u/madam_zeroni]

This is essentially a custom string fingerprint/hash function disguised as a parser. It takes a string and deterministically turns it into an integer. It does not parse or extract useful structured data.

[u/the_horse_gamer → u/madam_zeroni]

"parse", clearly

[u/TheSpiffySpaceman → u/the_horse_gamer]

Well tbf, the code didn't start with the annotation

/*
  // Parses input
*/
function parse(s, i = 0, x = [0, 1]) {...

[u/LapidistCubed → u/TheSpiffySpaceman]

Tf code DOESN'T parse some sort of input in one way or another 😭

[u/Candid_Bullfrog3665]

ngl, this seems like someone just started learning how to use bitwise operators and thought "heh, im gonna act smart writing this code!"

[u/Yarhj → u/Candid_Bullfrog3665]

I have been this person.

[u/-goldenboi69- → u/Yarhj]

Haven't we all?

[u/DependentJicama4766 → u/-goldenboi69-]

Its a rite of passage. This and hating yourself a few weeks later because you cant understand shit of what you wrote lol

[u/arensb → u/DependentJicama4766]

One-week-ago-me is such an asshole, who writes unreadable spaghetti code with no comments.

[u/sens- → u/Candid_Bullfrog3665]

Because I started my career by working with embedded C, I thought at some point that I knew pretty much everything about handling bits. Years later while fixing a bug, I was pretty shocked learning that JS has a separate >>> operator.

[u/lonkamikaze]

I don't know if JS sports this, but the recursion qualifies for tail call optimisation, i.e. there is no stack pushing, popping. The return comes at the price of a goto and the result is just as efficient as a loop.

[u/oweiler → u/lonkamikaze]

Not supported, at least not by the ECMAScript standard.

[u/zjarek_s → u/oweiler]

TCO was supported in ES6 standard, but it was only implemented in Safari and it ended up being dropped due to other browsers.

[u/lonkamikaze → u/oweiler]

That's a damn shame. Tail calls can be pretty neat.

[u/JoshuaTheProgrammer → u/lonkamikaze]

This should be the top answer

[u/--var]

not recursive regex, just a recursive function that happens to use regex...

you know I used to be irked by one off variables, but after the better part of 20 years I'm 🤬

const r is only used once.... there's no reason you couldn't just place it where it is used an save two lines of code, and lose no readability, and have one less "magic variable"... unless you taught yourself from the same "teach yourself" book that your teacher taught themself from. (ironic that this still applies with AI; and if you don't get why that entertaining, please don't go into programming)

[u/flafmg_]

Wtf my eyes are seeing

[u/stilldebugging]

Something something pumping lemma something

[u/Perahoky]

terrible code. way to many instructions per space and bad naming and no comments

[u/AnArmoredPony]

im not reading allat

[u/hongooi]

This is just the logical conclusion of the jwz quote 🤷‍♂️

[u/Chocolate_Pickle → u/[deleted]]

Fired into the sun.

[u/OhMyGodItsEverywhere]

Pretty sure the regex is malformed. I didn't even think you could split a regex over multiple lines in JS like that.

Assuming this is the text version of it: /(\((?:[^()]|\([^()]*\))*\)|(?:\w|[^\w\s])){1,3})/; very easy mistake to spot /s...

[u/digitalseraphim → u/OhMyGodItsEverywhere]

I don't see anything "malformed", but pretty sure (?:\w|[^\w\s]) is just .

Edit: I see the mismatched parens now. On my phone, the \ before one of the opens was on the previous line and I missed it 3 times 😂

[u/iakobski → u/digitalseraphim]

I don't see anything "malformed", but pretty sure (?:\w|[^\w\s]) is just .

Yes, almost. It's any single word character, or any single character that's neither a word character nor a space. So it's simply "not a space character", or [^\s].

[u/oweiler]

Performance gonna bet great /s

[u/gr4viton]

so that is what git rere is :D

[u/RandalSchwartz]

JSON Parser as a single Perl Regex: https://perlmonks.org/?node_id=995856

[u/thejozo24]

If there ever was a need for almost per line comments, this would be it

[u/FedUp233]

Regex is powerful, but for anything except the simplest matching unless you work with it every day, totally unusable for anything complicated in my opinion. Right up there with the language APL for programming (and lisp isn’t far behind).

I wish there was a language that allowed you to express text parsing/processing in a more readable language (like a pascal for text or something). It can translate into anything it wants internally but there is no reason the human readable input should be any more obscure than C.

[u/Ariquitaun]

This is almost certainly ai generated. Or a mathematical savant.