That Python is the output from this file: https://github.com/treeform/pixie/blob/master/bindings/bindi...
This is very new stuff for us but we really like the idea that we can generate comfortable bindings for many languages and never have to worry about method signatures or comments or default values getting out of sync with the C / shared lib interface.
Maybe I can write my loops in this and dip my toes this way? Good stuff, I'll be keen to see how it evolves.
Python always struggled with the “2 language problem” - you want something flexible and malleable to code in most of the time (-> usually slow) and something fast in small doses (-> usually rigid and compiled).
C/C++ is good but requires heavy scaffolding. Fortran has AFAIK good support, but it’s Fortran. There used to be an unholy and very useful utility called “scipy.weave” that lets you run inline C++, I think it was a coding abomination and now is gone.
The recommended way is using Cython, but I find it generally neither nice nor fast.
Nim could seriously be it for me.
"What do you mean, Nim has two of these already?"
Yeah, I know, and -- not to hurt anyone's feelings -- but: they kind of suck. And there's no way I see them able to be extended to do the job fully, based on the way they're currently built.
Those are some bold claims to make!
So before I get stoned to death (no offense to the authors, I am grateful that they exist and have used them both) let me attempt an explanation and back up these statements.
To start off, the two tools available are "c2nim" and "nimterop". c2nim is a Nim official library, while nimterop is a community library.
Consistently, what I heard was (roughly):
"If you want to programmatically interact with information about C/C++ units, you want to use the LLVM/clang ecosystem. You're going to think you can do what you want from 'libclang', the C API. But what you'll find out after sinking months of your time is that libclang DOESN'T expose enough info about the AST for certain scenarios, and there is ABSOLUTELY ZERO WAY to get it. So you'll need to use libTooling, which is C++, and has the full AST available."
Most notably is Tanner Gooding & Co's "libClangSharp" from the Microsoft "ClangSharp" project, and PathogenDavid's "Biohazrd" libraries (which again are a sort of enhanced fork based on ClangSharp):
https://github.com/microsoft/ClangSharp # See "/sources/libClangSharp"
- c2nim is a custom C lexer/parser written in Nim, with zero support for C++
- nimterop uses tree-sitter, which isn't bad but it's certainly no "libTooling"
Nimterop is also dead as far as I understand -- last active commit period was about ~1 yr ago.
I'm hard to convince to the path to success here doesn't involve leaning on the collective decades of man-hours of engineering put into clang/LLVM. C++ is a nightmare of a specification, a veritable cluster-fuck of complexity.
As a side note, I've had the opportunity to speak to one of the Nim maintainers (Timothee Cour) about this and the future here, and he's expressed interest in having a good story for easy type-safe C++ interop via binding generation and also believes it's important.
So hopefully this is something we'll see pop up eventually.
Maybe I'll take a crack at myself using ClangSharp (or it's XML output format, using TypeScript/Python to munge the XML and spit out code) but there aren't enough hours in a day to do all the interesting things =(
Though I’ve had good luck with just c2nim. But as you mention it’ll break on some corner cases things, so I just tweak the C a bit (remove function attributes, etc) then retry. However, c2nim was recently updated and fixed a bunch of C99 things. I haven’t had to do that in a while.
If you wanted to go this route, using ClangSharp's XML output would probably be easier because it's been tailored to extract the "useful" bits and to expose some of the info that is hard to get at from a raw AST dump