Extending Python with Rust calls

rust2python.md

What is Rust?

'A systems programming language that runs blazingly fast, prevents segfaults, and guarantees thread safety.' So think of it as C/C++ with out all the scariness, and we can extend Python for all our critical computation.

Install Rust

yaourt -S rust

Build new Rust library with cargo

cargo new pycall

Your Rust project has been created in the pycall directory

Once you have modified your Rust file in /src :

rustc src/lib.rs

Now that you have compiled your shared library you can hook to it in your Python Script

Run your Python Script

pypy pycall.py

<cffi.api.FFILibrary_src/liblib.so object at 0x0000000001130020>
20000

lib.rs

#![crate_type = "dylib"]

#[no_mangle]
pub extern fn rustex(x: i32) -> i32{
    x * 2
}


#[test]
fn it_works() {
    assert!(rustex(2) == 4)
}

pycall.py

try:
    from cffi import FFI
except ImportError:
    print "pip install cffi, included with PyPy"

ffi = FFI()
lib = ffi.dlopen("src/liblib.so")

print lib


ffi.cdef('int rustex(int);')

print lib.rustex(10000)