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?

@krassowski: If I tell setup not to build the C++ stuff, then the functions expose automatically. I think two packages are getting declared and PyBind is taking precedence. But I will check on your suggestion shortly. — Richard
– Richard, Commented Aug 12, 2017 at 3:03

Richard · Accepted Answer · 2017-08-17 01:47:53Z

2

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
)

answered Aug 17, 2017 at 1:47

Richard

62.8k40 gold badges198 silver badges277 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Benjamin Maier Over a year ago

currently having the same problem ... using this answer, are you able to call bob.myfunc() now or do you have two packages installed now?

Richard Over a year ago

@BenjaminMaier: I see that I've answered the question less clearly than I could have. What I do now when I want a package named bob is to compile the pybind11 code into a package named _bob and then in __init__.py I import a bunch of stuff from _bob to make it available in bob.

Collectives™ on Stack Overflow

Mixing Python and C++ source files in pybind11

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related