[C++-sig] conversion problem

[Luca Sbardella]

I substituted the convert method in pair_to_tuple with the following

     static PyObject* convert(ctype const& v)  {
            using namespace boost::python;
            list values;
            values.append(v.first);
            values.append(v.second);
            return incref(tuple(values).ptr());
        }

And this works in all situations. However, I admit it is not a great
solution.

2008/12/11 Luca Sbardella <luca.sbardella at gmail.com>

> My authomatic conversion function from std::pair does not work when one of
> the pair type is a boost::python::object.
>
> Template for conversion
>
> template<class K, class T>
> struct pair_to_tuple  {
> typedef pair_to_tuple<K,T> converter;
> typedef std::pair<K,T> ctype;
>
> static PyObject* convert(ctype const& v)  {
> using namespace boost::python;
> return incref(make_tuple(v.first,v.second).ptr());
> }
> static void register_to_python()  {
> boost::python::to_python_converter<ctype,converter>();
> }
>      };
>
>
>
>
> using namespace boost::python;
> pair_to_tuple<double,object>::register_to_python();           <---------
> FAILED
> pair_to_tuple<double,std::string>::register_to_python();     <--------- OK
>
> The error I get is
> *error C2668: 'boost::python::make_tuple' : ambiguous call to overloaded
> function
> could be 'boost::python::tuple boost::python::make_tuple<_Ty1,_Ty2>(const
> A0 &,const A1 &)'**
> or       'boost::tuples::tuple<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9>
> boost::tuples::make_tuple<_Ty1,_Ty2>(const T0 &,const T1 &)' [found using
> argument-dependent lookup]
> *
> What I'm I doing wrong?*
> *
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