====== RustとPythonの様子見 ======

作成日: 2023-08-12 (土)

[[https://youtu.be/5A9lpLZy_rQ|第7回 RustとPythonの様子見]]

プロジェクトレイアウト
  .
  └── example/
      ├── Cargo.toml
      └── src/
          └── lib.rs

===== example =====

rust-cpythonを使ったPythonの拡張モジュール。

==== Cargo.toml ====

<file toml>
[package]
name = "foo"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]

[lib]
name = "foo"
crate-type = ["cdylib"]

[dependencies.cpython]
version = "0.7"
features = ["extension-module"]
</file>

==== src/lib.rs ====

<file rust>
extern crate cpython;

use cpython::{py_fn, py_module_initializer, PyNone, PyResult, Python};

py_module_initializer!(foo, |py, m| {
    m.add(py, "__doc__", "A module written in Rust.")?;
    m.add(py, "greet", py_fn!(py, greet_py(name: &str)))?;
    m.add(py, "add", py_fn!(py, add(a: i32, b: i32)))?;
    Ok(())
});

fn greet(name: &str) {
    println!("Hello, {}!", name);
}

fn greet_py(_py: Python, name: &str) -> PyResult<PyNone> {
    greet(name);
    Ok(PyNone)
}

fn add(_py: Python, a: i32, b: i32) -> PyResult<i32> {
    let out = a + b;
    Ok(out)
}
</file>