[C++-sig] variable argument number and BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS

Hans Roessler hansroessler at yahoo.de
Thu May 21 15:39:58 CEST 2009

I try to wrap a class with a function info([int arg]) that takes either zero or one argument (exact colde below). For some reason I can't get BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS to work.

The examples at http://www.boost.org/doc/libs/1_39_0/libs/python/doc/tutorial/doc/html/python/functions.html#python.overloading and
http://www.boost.org/doc/libs/1_39_0/libs/python/doc/v2/overloads.html#BOOST_PYTHON_FUNCTION_OVERLOADS-spec only show the situation where either
- the *member* function has up to three arguments with default values assigned or
- three *free* functions have one to three  arguments.

I don't find an example where a class has several *member* functions with the same name, that take a variable number of (non-default!) arguments.

My attempt below gives the error
"pytest.cpp:17: error: no matching function for call to ‘boost::python::class_<A, boost::python::detail::not_specified, boost::python::detail::not_specified, boost::python::detail::not_specified>::def(const char [5], <unresolved overloaded function type>, A_info_overloads)’"

Do I have to replace the ".def("info",&A::info, ..." with something like  ".def("foo", (void(*)(int,int))0, ..." as shown in the Auto-Overloading section in the tutorial? If yes, how must this function signature look like? It doesn't work like this.

Hope someone can help

=== pytest.py ===
#include <boost/python.hpp>
#include <stdio.h>

using namespace boost::python;

class A{
  void info() {printf("This is an A\n");}
  void info(int arg) {printf("Unnecessary arg.\n");}


      .def("info",&A::info,A_info_overloads()) //line 17


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