Automatically generate PyBind11 code for Python wrapping C++ projects.

cppwg/shapes/ is a full example project, demonstrating how to generate a Python package pyshapes from C++ source code. It is recommended that you use it as a template project when getting started.

As a small example, we can start with a free function in cppwg/shapes/src/math_funcs/SimpleMathFunctions.hpp:

#ifndef _SIMPLEMATHFUNCTIONS_HPP
#define _SIMPLEMATHFUNCTIONS_HPP

/**
 * Add the two input numbers and return the result
 * @param i the first number
 * @param j the second number
 * @return the sum of the numbers
 */
int add(int i, int j)
{
    return i + j;
}

#endif  // _SIMPLEMATHFUNCTIONS_HPP

add a package description to cppwg/shapes/wrapper/package_info.yaml:

name: pyshapes
modules:
- name: math_funcs
  free_functions: cppwg_ALL

and do python cppwg/shapes/wrapper/generate.py (with some suitable arguements).

The generator will make the following PyBind wrapper code in cppwg/shapes/wrapper/math_funcs/math_funcs.main.cpp:

#include <pybind11/pybind11.h>
#include "wrapper_header_collection.hpp"

namespace py = pybind11;

PYBIND11_MODULE(_pyshapes_math_funcs, m)
{
    m.def("add", &add, "");
}

which can be built into a Python module and (with some import tidying) used as follows:

from pyshapes import math_funcs
a = 4
b = 5
c = math_funcs.add(4, 5)
print c
>>> 9

It is recommended that you learn how to use PyBind11 first. This project just generates PyBind11 wrapper code, saving lots of boilerplate in bigger projects.

Developed and tested with Python 3 on Ubuntu 18.04.

• Download the CastXML binary (available here)
• Install Python dependencies pip install pygccxml pyyaml
• Clone cppwg with git clone https://github.com/jmsgrogan/cppwg.git

To generate the full pyshapes wrapper do:

git clone https://github.com/jmsgrogan/cppwg.git $CPPWG_DIR
python $CPPWG_DIR/shapes/wrapper/generate.py --source_root $CPPWG_DIR/shapes/src/ --wrapper_root $CPPWG_DIR/shapes/wrapper/ --castxml_binary castxml/bin/castxml --package_info $CPPWG_DIR/shapes/wrapper/package_info.yaml --includes $CPPWG_DIR/shapes/src/

then to build the example package do:

mkdir $BUILD_DIR
cd $BUILD_DIR
cmake $CPPWG_DIR/shapes
make

To test the resulting package do:

python test_functions.py 
python test_classes.py 

• Make a wrapper directory in your source tree mkdir $WRAPPER_DIR
• Copy the template in cppwg\shapes\wrapper\generate.py to $WRAPPER_DIR and fill it in.
• Copy the template in cppwg\shapes\wrapper\package_info.yaml to $WRAPPER_DIR and fill it in.
• Do python $WRAPPER_DIR\generate.py to generate the PyBind11 wrapper code in $WRAPPER_DIR.
• Follow the PyBind11 guide for building with CMake, using cppwg\shapes\CMakeLists.txt as an initial guide.