Ticket #9687: make_method.hpp

// Copyright 2014, Peter Hatina <phatina@redhat.com>
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef MAKE_METHOD_HPP
#define MAKE_METHOD_HPP

#include <boost/python/extract.hpp>
#include <boost/python/dict.hpp>
#include <boost/python/object/py_function.hpp>
#include <boost/python/raw_function.hpp>
#include <boost/python/tuple.hpp>
#include <boost/mpl/vector/vector10.hpp>
#include <boost/limits.hpp>

namespace boost { namespace python {

namespace detail {

template <typename C, typename M>
class raw_method_dispatcher
{
public:
    raw_method_dispatcher(M method): m_method(method) {}

    PyObject* operator()(PyObject* args, PyObject* kwds)
    {
        detail::borrowed_reference_t *rargs = detail::borrowed_reference(args);
        object args_obj(rargs);

        // Extract a C++ reference to object, which is about to call raw method
        C &obj = extract<C&>(object(args_obj[0]));

        // Return boost::python object containing the raw method call
        return incref(
            object(
                (obj.*m_method)(
                    tuple(args_obj.slice(1, len(args_obj))),
                    kwds ? dict(detail::borrowed_reference(kwds)) : dict())
                ).ptr()
            );
    }

private:
    M m_method;
};

}

template <typename C, typename M>
object raw_method(M method, std::size_t min_args = 0)
{
    return detail::make_raw_function(
        objects::py_function(
            detail::raw_method_dispatcher<C, M>(method),
            boost::mpl::vector1<PyObject*>(),
            min_args,
            (std::numeric_limits<unsigned>::max)())
    );
}

}}

#endif // MAKE_METHOD_HPP