A new C++ back end for ocamlc
Comments
QuadmasterXLII
anitil
> Using these more sophisticated data structures, g++ is able to compute the prime numbers below 10000 in only 8 seconds, using a modest 3.1 GiB of memory.
Finally, I can get some primes on my laptop!
foltik
> which produces primes.cpp, containing your program translated to idiomatic, readable C++ code:
As a C++ enjoyer I can confirm this is some excellent idiomatic, readable C++ code.
sheepscreek
Most of it yes, but what about:
typedef I<((I<((n::val (p::val))>::val) != (I<0>::val))> res;
};
There is some top class wizardry going on there! I don’t think I’ve ever used conditions in a type definition in C++ :)Update:
Ah, alright - so that evaluation logic is part of the template, not the code that eventually compiles.
It’s basically offloading some of the higher level language compiler logic to the templating engine. Honestly might be a better time investment than spending more time writing this in the parser.
Now I’m sort of intrigued and inspired to use C++ as a lowering target for elevate (a compiler framework I’ve been working on).
dnmc
Is this the Stephen Dolan of "mov is Turing Complete" fame?
LeonidasXIV
Yes, its exactly that Stephen Dolan.
loeg
I believe so.
blanched
My eyebrows raised at "C++ is a purely functional language", but I thought it was just a typo.
The rest is fantastic, and I'm glad it wasn't a typo.
zorobo
This made my day, thank you!
classified
> C++ is a purely functional language, with no support for mutable state.
> To run a C++ program, you'll need a C++ interpreter.
I thought 1. April is already over?
ajbt200128
Wow Stephen Dolan never fails to impress
Caum
[flagged]
fayash
Might have missed the joke here. This isn't a traditional C++ backend; it's a C++ Template Metaprogramming backend. The code isn't meant to be run—it’s meant to be compiled. The "output" you see is actually just a compiler error message because the program forces the compiler to calculate primes during type checking. The "runtime performance" the author mentioned is actually just how long g++ takes to crash your ram.
kristjansson
Per TFA C++ is a purely functional, interpreted language. Should be trivial to embed into?
tux3
This account is low-effort spam, the LLM generated comment seems to only look at the title. They should at least feed the contents of the page to the AI if they're going to spam.
ygritte
Accounts like that should be deleted.
hudsonhs
She (Jane Street) is not gonna notice you, bro
shorsher
I believe they already work for Jane Street.
binarycrusader
znpy
Interesting fact: it was recently "revealed" in a podcast episode by Bryan Cantrill that Jane Street was one of the early customer of the Oxide Computer company.
Brilliant stuff. A tip for writing long-running C++: bizzarely, the C++ interpreter completely lacks tail call optimization. As a result, most idiomatic C++ code implements and uses reverse, map, range, filter etc, which don’t blow the stack if you implement them like (forgive the pseudo-code)
Whoever has to maintain your code after you are gone will apprrciate that you used the idiomatic, portable approach instrad of relying on command line flags.