id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
6203,boost::python::api::object constructor failure,Johan Råde <johan.rade@…>,Ralf W. Grosse-Kunstleve,"Here is the C++ code for a Python extension module and a Python script that calls the module.
Expected behavior when you run the script:
{{{
The script runs and produces the output ""Hello, I'm Y!""
}}}
Observed behavior (with Boost 1.48.0, Python 2.7.2, MSVS 2010):
{{{
The script fails with the error message:

Traceback (most recent call last):
  File ""../TestHello/TestHello.py"", line 12, in <module>
    y = Hello.create('Y')
TypeError: No to_python (by-value) converter found for C++ type: class Y
Press any key to continue . . .
}}}

I have also attached a zip file with the code as a solution for MSVS 2010 and Python Tools for Visual Studio.

Hello.cpp:
{{{
#include <string>
#include <exception>
#include <boost/noncopyable.hpp>
#include <boost/python.hpp>

using std::string;
using boost::noncopyable;
using boost::python::class_;
using boost::python::def;

class X : noncopyable {
public:
    string hello() const { return ""Hello, I'm X!""; }
};

class Y : noncopyable {
public:
    string hello() const { return ""Hello, I'm Y!""; }
};

class Z : noncopyable {
public:
    string hello() const { return ""Hello, I'm Z!""; }
};

PyObject* create(char c)
{
    if(c == 'X')
        return boost::python::api::object(new X).ptr();
    else if(c == 'Y')
        return boost::python::api::object(new Y).ptr();
    else if(c == 'Z')
        return boost::python::api::object(new Z).ptr();
    else
        throw std::exception(""The function argument must be 'X', 'Y' or 'Z'."");
}

BOOST_PYTHON_MODULE(Hello)
{
    class_<X, noncopyable>(""X"").def(""hello"", &X::hello);
    class_<Y, noncopyable>(""Y"").def(""hello"", &Y::hello);
    class_<Z, noncopyable>(""Z"").def(""hello"", &Z::hello);

    def(""create"", &create);
}
}}}

Test.py:
{{{
import Hello
y = Hello.create('Y')
print(y.hello())
}}}
",Bugs,closed,To Be Determined,python USE GITHUB,Boost 1.48.0,Problem,invalid,,