...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Exposing Classes |
Now let's expose a C++ class to Python.
Consider a C++ class/struct that we want to expose to Python:
struct World
{
void set(std::string msg) { this->msg = msg; }
std::string greet() { return msg; }
std::string msg;
};
We can expose this to Python by writing a corresponding Boost.Python C++ Wrapper:
#include <boost/python.hpp>
using namespace boost::python;
BOOST_PYTHON_MODULE(hello)
{
class_<World>("World")
.def("greet", &World::greet)
.def("set", &World::set)
;
}
Here, we wrote a C++ class wrapper that exposes the member functions greet and set. Now, after building our module as a shared library, we may use our class World in Python. Here's a sample Python session:
>>> import hello
>>> planet = hello.World()
>>> planet.set('howdy')
>>> planet.greet()
'howdy'
Copyright © 2002-2003 David Abrahams
Copyright © 2002-2003 Joel de Guzman
Permission to copy, use, modify, sell and distribute this document
is granted provided this copyright notice appears in all copies. This document
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