boost.python

最近工作中使用到boost.python，感觉网上这方面的资料还是比较少，官方文档写的也不够详尽，算是做个备忘吧

const char* greet()
{
    return "hello,world";
}
// operator= for index

typedef std::vector<int> VI;
struct Foo
{
    int32_t a;
    std::string b;
    VI vi;
    bool operator==(Foo const& f) const { return f.a == a; }
};

// A friendly class.
typedef std::vector<Foo> VecFoo;
class hello
{
public:
    hello(const std::string& country) { this->country = country; }
    std::string greet() const { return "Hello from " + country; }
    Foo get_foo()const
    {
        Foo foo;
        foo.a = 123;
        foo.b = country;
        return foo;
    }
public:
    std::string country;
    VecFoo vf;
};

template <typename T>
struct VecConvert
{
    typedef std::vector<T> VecT;
    static PyObject* convert(const VecT& vt)
    {
        boost::python::list pylist;
        for (auto& t : vt)
        {
            pylist.append(t);
        }
        return boost::python::incref(pylist.ptr());
    }
};    

• 导出函数及POD结构

  boost::python::def("greet", greet);
  boost::python::class_<Foo>("Foo")
      .def_readwrite("a", &Foo::a)
      .def_readwrite("b", &Foo::b)
      .def_readwrite("vi", &Foo::vi);
  

• 导出类

  boost::python::class_<hello>("hello", init<std::string>())
      // Add a regular member function.
      .def("greet", &hello::greet)
      // Add invite() as a member of hello!
      .def("invite", invite)
      .def("get_foo", &hello::get_foo)
      .def_readwrite("vf", &hello::vf);  
  

• 导出容器
  1. 导出一个新的容器类

     boost::python::class_<VI>("VI").def(boost::python::vector_indexing_suite<VI>());
     

  2. 直接转换为python的list

     boost::python::to_python_converter<VI, VecConvert<int>>();
     

• python list对象转换为c++ vector

  //c++
  void setFoos(const boost::python::list& pylist)
  {
      std::vector<Foo> fs;
      for (int i =0; i< boost::python::len(pylist); i++)
      {
          fs.push_back(boost::python::extract<Foo>(pylist[i]));
      }
  }
  boost::python::def("setFoos", setFoos);
  //python
  Foo f1,f2
  setFoos([f1, f2])