Add a simple example about how to build your own C++ Pyodide package

📚 Documentation

I saw that there is already a page on the Pyodide website titled “Creating a Pyodide package”, but for a C/C++ developer it is not clear how to proceed.

In my conversation here, @JeanChristopherMorinPerso informed me that it is possible to create Pyodide packages from C++ code that has the Pybind11 wrapper and that he made it himself for his project.

My C++ library already has the Pybind11 wrapper, but even so, I’m not finding documentation or a simple example that I can follow and get a valid Pyodide package.

Finally, I tried to understand what was the reasoning behind compiling Pyodide packages which were originally written in C/C++ contained on Github in the ‘packges’ folder, (example: ‘numpy’), but I couldn’t understand the logic of the contents of these folders and how everything is actually working.

So for libraries written in C/C++ I have 2 suggestions:

Suggestion 01: C++ code without Pybind11 wrapper

Adding to the documentation (maybe even in the README) is a simple little example of how to create a Pyodide package from a C++ library. This simple example could be named: Hello World.

Example:

#include <iostream>

class HelloWorld
{
public:
    HelloWorld() {
        std::cout << "Hello" << std::endl;
    }
}

Suggestion 02: Code with Pybind11 wrapper

Add the same type of simple example mentioned above to the documentation but that contains a Pybind11 wrapper

[josephrocca]

Question 01: Did you mean that I should create a new package inside Pyodide folder containing pure C++ code? As my “Hello World” above? Question 02: If yes, should I write the Pybind11 wrapper too? Or do you prefer the only pure C++ class?

What I had in mind is that you’d create a Python package that uses C++ and Pybind11 like you normally would (I.e. ignore the Pyodide aspect). You’d just create this package in a new Github repo, and then publish the package to PyPi, and then run the commands in this comment sequentially, where <package-name> is the name of the PyPi package that you published.

IIUC, that should work “out of the box” for simple C++/Python packages. If it doesn’t, then we can troubleshoot from there and add extra steps to the “hello world” tutorial that we write.

[hoodmane]

it is not easy for new contributors to add a package that uses CMake

Nor is it easy for me. My approach is to ask henryiii or ryanking13.