Re: [pygccxml-development] Exposing boost::python::list

[Scott S. <sc...@bi...>]

As a follow on, I did get this to work by using an actual list, and not a 
pointer to one.  So the pseudocode becomes:

#pramga once
#ifndef __GCCXML__
#include <boost/python.hpp>
typedef boost::python::list list;
#else
class list {};
#endif

class MyClass {
   public list mylist;
   MyClass() { mylist.append(1); }
};

Then in python, I have no problems:

>>> mc.mylist
[1]
>>> mc.append(2)
>>> mc.mylist
[1,2]

Thanks,

Scott


On Mon, 1 Aug 2011, Scott Sturdivant wrote:

> Hi,
>
> I'd like to have a class which as a boost::python::list as a public 
> attribute.  I know that gccxml cannot parse boost/python.hpp, so given a 
> suggestion on the mailing list archives, I have done the following:
>
> #pragma once
> #ifndef __GCCXML__
> #include <boost/python.hpp>
> typedef boost::python::list list;
> #else
> class list;
> #endif
>
> class MyClass {
>  public:
>    list * mylist;
> };
>
> MyClass::MyClass()
> {
>  mylist = new boost::python::list();
>  mylist.append(1);
> }
> MyClass::~MyClass()
> {
>  delete mylist;
> }
>
> Py++ is able to create the bindings and it compiles fine.  However, when 
> accessing the 'mylist' attribute in python, I'm seeing the following 
> behavior:
>
>>>> print type(myclass.mylist)
>
>>>> print type(myclass.mylist)
> Traceback (most recent call last):
>  File "<stdin>", line 1, in <module>
> TypeError: cannot create weak reference to 'list' object
>>>> print type(myclass.mylist)
> Fatal Python error: GC object already tracked
> Aborted
>
> I think I'm going about this the wrong way, but am unsure of the proper way. 
> Would this be a use case for the 'inserting_code' functionality of py++?
>
> Thank you!
>
> Scott
>