[C++-sig] Inherited instance variables

[David Abrahams]

Matt Giger <mgiger at lunarsoft.com> writes:

> Hi, I just discovered Boost.Python and I am very impressed (as I am
> with most of Boost). I have embedded a Python interpreter in my
> project and would like to tie in some C++ classes but am having
> problems with inherited member variables.

Matt, are you using Boost 1.29.0 or the CVS?  There have been some
improvements in handling of mutable attributes.

> Here is my example:
>
> C++
> ---
>
> struct foo {
>    foo(void) {}
>    virtual ~foo(void) {}
>    virtual bool handle_evt(object event) { return false; }
>    list children;
> }
>
> struct foowrap : foo {
>    foowrap(PyObject* self) : self_(self) {}
>    foowrap(PyObject* self, const foo& f) : foo(f), self_(self) {}
>    bool handle_evt(object event)
>     { return call_method<bool>(self_, "handle_evt", event); }
>    static bool def_handle_evt(foo* f, object event)
>     { return f->foo::handle_evt(event); }
>    PyObject* const self_;
> };
>
> BOOST_PYTHON_MODULE(foomod)
> {
>    class<foo, foowrap>("foo")
>     .def("handle_evt", &foowrap::def_handle_evt)
>     .def_readwrite("children", &widget::children);
> }

This won't compile; where's widget?


...

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com