Hi,

I have a c++ class T that I succesfully expose via:

class_<T, T*> ...

later on, I have

struct S {   const T* underlying; };

class_<S,S*>("S").     .def_readonly("underlying", &S::underlying) ;

From python, when I call:

s.underlying

where s is a python instance of S, i get the following error:

TypeError: No to_python (by-value) converter found for C++ type: T const*

Do I need another converter for T const* in particular? or for both T* and T const*? Does the class_<T,T*> above only expose T itself, not pointers to it?

Using add_property() instead should be your friend, to be able to use a call policy. E.g.: #include <boost/python.hpp> namespace bp = boost::python; // classes to expose struct A { }; struct B { B() : underlying(NULL) { } A const * underlying; }; // expose to python BOOST_PYTHON_MODULE(properties) { bp::class_<A>("A") ; bp::class_<B>("B") // Won't work: "No to_python (by-value) converter found... //.def_readonly("underlying", &B::underlying) .add_property("underlying", bp::make_getter(&B::underlying, bp::return_internal_reference<>())) ; } See FAQ entry also: http://www.boost.org/doc/libs/1_59_0/libs/python/doc/v2/faq.html#topythoncon... Holger Landesbank Baden-Wuerttemberg Anstalt des oeffentlichen Rechts Hauptsitze: Stuttgart, Karlsruhe, Mannheim, Mainz HRA 12704 Amtsgericht Stuttgart