Mixing Python and C++ source files in pybind11

Question

I am using PyBind11 to make a Python project.

My directory structure looks a like this:

./
  my_pkg/
    __init__.py
    func1.py
    func2.py

My C++ code looks like this:

int myfunc(){
  return 1;
}

PYBIND11_PLUGIN(cppmodule) {
  py::module m("cppmodule", "My cpp module");

  m.def("myfunc",&myfunc,"This does stuff");

  return m.ptr();
}

And my setup.py looks like this:

from setuptools import setup, Extension
import glob

ext_modules = [
  Extension(
    "cppmodule",
    glob.glob('src/*.cpp'),
    include_dirs       = ['lib/include', 'lib/pybind11/'],
    language           = 'c++',
    extra_compile_args = ['-std=c++17'],
    define_macros      = [('DOCTEST_CONFIG_DISABLE',None)]
  )
]

setup(name = 'bob',
  version      = '0.1',
  description  = 'A package about shrimp',
  url          = 'http://github.com/shrimp',
  author       = 'Bob',
  author_email = '',
  license      = 'MIT',
  ext_modules  = ext_modules
)

Now, if I runn

python setup.py install

everything compiles.

But here's the odd part, later, I can run import cppmodule but not import bob. Or, with other fiddling, sometimes I can run both.

What I have not figured out how to do, but what I would like to do, is to have the C++ code incorporated into the bob module the same way func1 and func2 will be, so that I can type bob.myfunc() in Python.

How can I do this?

Answer 1

The answer was to modify the code in setup.py to look like:

from setuptools import setup, Extension, find_packages

setup(name = 'bob',
  version      = '0.1',
  description  = 'A package about shrimp',
  url          = 'http://github.com/shrimp',
  author       = 'Bob',
  author_email = '',
  license      = 'MIT',
  packages     = find_packages(),
  ext_modules  = ext_modules
)