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Comment by lqdc13 | Hacker News Reader

I'm using Nim's Pymod https://github.com/jboy/nim-pymod for this exact purpose and I think it's much better suited.

The reason is that it can automatically generate C API code without FFI, because FFI calls are slower (https://gist.github.com/brentp/7e173302952b210aeaf3) so there is less overhead. You obviously care about overhead here.

Nim's pymod is already a python module and you can send strings and numpy arrays to Nim for fast processing.

I wish you could send bytes from python3, but that's not implemented yet.

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There's rust-cpython that works like this: https://github.com/dgrunwald/rust-cpython/

I'm really not anfan of linking libpython if I can avoid it. More wheels to build and then its limited to cpython. Cffi is plenty fast.

Which method do you find easiest (read: least developer time) for using large rust codebases from Python?

CFFI works quite well. I will probably make a post on my blog later with some ideas on how to do it.

Not only does it work well, it is portable across nearly all Pythons you would want to use, CPython and PyPy.

Can you import that as a lib in Python to work in reverse? It seems to be a different use-case otherwise - using a Python library from Rust vs optimizing a hotspot within Python.

This page claims you can: http://ehiggs.github.io/2015/07/Python-Modules-In-Rust/

I've looked at Nim a bit, and it does have some nice features. But magic identifier equality [1] is an intrinsically disqualifying design choice.

> If a language's lexical structure is so tortured that I need a special tool to grep it, I'm going to skip it and go back to the sanity of C++. [2]

Nope, nope, no way.

[1] http://nim-lang.org/docs/manual.html#lexical-analysis-identi... [2] https://news.ycombinator.com/item?id=8936542

I only used nim for some side projects but the only times I saw this used anywhere is in FFI bindings.

That way you can mirror, say, C style while writing the bindings either manually or automatically and use them as if they were normal nim elsewhere.

Do you have experience with cython? If so, how does Nim compare for writing fast C extensions?

Since you can basically write C in Cython, it depends how far you take the cython optimization. You can just add a few types, or you can go nuts via scipy's BLAS interface https://github.com/RaRe-Technologies/gensim/blob/develop/gen...

In general, you can get to less overhead with Cython right now because it's a much more mature project and because you can be more flexible with defining the point where you drop from python to a faster alternative. I wouldn't use that Nim/Python lib in production unless you have time to help with its development. It's good for personal projects though.

My personal experience with cython (and why I'm less than lukewarm about it) is that it's about as much fun as C to write and only really helps wih he annoyance of dealing with PyObject. That's something that was not even required for the sourcemap lib.

Debugging and writing cython that is fast is feally not a very pleasant experience and the tooling is not great. Let alone that a real ecosystem exists. There is not even a good way to deal with dependencies at compile time.

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