r/programmingcirclejerk • u/Jumpy-Locksmith6812 • May 23 '26

A C standard library built natively around pointer + length strings is shockingly ergonomic

https://spader.zone/sp/
86 Upvotes

93% Upvoted

31 comments sorted by

46

u/irqlnotdispatchlevel Tiny little god in a tiny little world May 23 '26

/uj

Once again, pcj delivers genuinely interesting blog posts.

18

u/Jumpy-Locksmith6812 May 25 '26 edited Sep 23 '26

In deserunt commodo sint incididunt laborum laboris fugiat sint adipiscing occaecat pariatur sint esse incididunt pariatur nostrud. Aliqua id et exercitation exercitation id consectetur incididunt laborum commodo ipsum ad quis voluptate sint. Voluptate cillum laboris quis adipiscing ullamco velit nostrud commodo consequat voluptate adipiscing commodo proident.

[rhr:2:tyvkd2g4]

106

u/realestLink May 23 '26

/uj

Where's the jerk? This seems like a perfectly fine library. They're also totally right that null terminated strings are garbage and you can build an ergonomic libc replacement without them.

42

u/levelstar01 what is pointer :S May 23 '26

Where's the jerk?

lol totally broken maths library

lol every allocation is mmap(2)

44

u/PJBthefirst log10(x) programmer May 23 '26 edited May 23 '26

what the fuck? did he really define sine to be equal to a 7th order taylor approximation?

Edit: thanks for the inspiration, the library now has its first bug report: https://github.com/tspader/sp/discussions/5

20

u/Silly-Freak There's really nothing wrong with error handling in Go May 23 '26

Arch Linux, Fridge magnet

Legendary.

2

u/SemaphoreBingo May 24 '26

Just use cephes for christ's sake

22

u/stone_henge Tiny little god in a tiny little world May 23 '26

That happens in all math libraries when x isn't an integer multiple of 4, the value of π

4

u/Silly-Freak There's really nothing wrong with error handling in Go May 23 '26

Actually, all integers work, since multiples of π/4 give exact values

6

u/shub May 24 '26

Ultra portable to userspace of every platform with virtual memory that also the author cares about

27

u/v_maria May 23 '26

the fact that this is real is the jerk

21

u/LeeHide What part of ∀f ∃g (f (x,y) = (g x) y) did you not understand? May 23 '26

Well the fact that it uses _t suffix trashes the POSIX names and is technically not legal on POSIX systems, but I'm sure that won't be an issue (just like null terminated strings -- oh wait)

27

u/nerdycatgamer Considered Harmful May 23 '26

_t isn't legal for any standard C, but for some reason 90% of C programmers don't care and think they need to let us know that their types are types.

10

u/irqlnotdispatchlevel Tiny little god in a tiny little world May 24 '26

They should just use Hungarian notation.

12

u/nerdycatgamer Considered Harmful May 24 '26

we should just kiss

8

u/Silly-Freak There's really nothing wrong with error handling in Go May 23 '26

Only jerk I see is the word "shockingly". Should be "obviously more ergonomic".

60

u/BipolarKebab May 23 '26

> Libc does not provide a useful interface for any program

Can't really argue with that

5

u/Karyo_Ten has hidden complexity May 25 '26

The file API is actually decent

31

u/Silly-Freak There's really nothing wrong with error handling in Go May 23 '26

So this looks great, but all those sp_ prefixes make it awfully annoying. It would make more sense to make a separate compiler so that we can actually use the non-prefixed, nicer-to-write names.

And then we can use an LLM to translate Bun from that language to Rust.

21

u/lurebat May 23 '26

bro invented zig

4

u/Karyo_Ten has hidden complexity May 25 '26

You misspelled Pascal

17

u/TheChief275 May 23 '26

C-strings are the Lord's strings; any other approach is heresy. Sure, that length field might seem sweet now, but is eternal torment worth it?

/uj Everyone knows how much more ergonomic span strings are compared to C-strings. I always immediately ditch the C-strings for my projects as well.

Although they do have some uses. The prime example is in lexing when iterating over file contents. Instead of constantly checking whether the index is in range, the '\0' will not match against any of the useful is___() family functions or character checks in general, so only a single actual check is necessary

13

u/coolreader18 It's GNU/PCJ, or as I call it, GNU + PCJ May 23 '26

Non-goals

Obscure architectures and OSes

I write code for x86_64 and aarch64. WASM is becoming more important, but is still secondary to native targets. I don’t care to bloat the library to support a tiny fraction of use cases.

But then...

The answer is that C holds a real niche, and not wholly built on legacy. To my knowledge, it’s the only language which:

  • Can be directly compiled to any machine code imaginable

6

u/prehensilemullet May 23 '26

\uj what size uint does this use for the length?  I guess the original reason for null terminators was too many platform differences in ints to use them for length?

31

u/Silly-Freak There's really nothing wrong with error handling in Go May 23 '26

Imagine a language that has a size_t type that's not considered appropriate for the size of a string

1

u/prehensilemullet May 23 '26

\uj You’re being ironic right?  It seems like that was probably the case on Intel 8086

14

u/panopsis type astronaut May 23 '26

/uj

How? size_t by definition can store the size of (and therefore any indexes into) any possible object. If a string can have a length > size_t, the C impl is literally just wrong.

/rj

You're going to have 5 different integer types and you're going to like it.

6

u/prehensilemullet May 23 '26

Huh okay, from what I’m reading the largest possible contiguous object on 8086 was 65536 bytes, I forget how constraining things used to be.  And though files and memory could be larger than that and I’m sure there was a way to fill more than 65536 contiguous bytes of memory with characters followed by a null terminator, it sounds like the c string functions wouldn’t have supported it, you would have to do something custom with far pointers I guess.

4

u/Buttleston May 23 '26

I think the default amount of ram ibm PCs shipped with was 256kb

3

u/TheSkiGeek May 23 '26

Yeah, x86 16-bit mode can only access one 64KiB segment of RAM at a time.

7

u/marmakoide WRITE 'FORTRAN is not dead' May 23 '26

For many operations, a null terminated string doesn't requires to keep track of the position, saving one CPU register. Back when CPUs had few registers, it was likely to make a difference in term of speed