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    copied!<p>I think I found the solution. Going through the example I quoted on my ask, and also the boost documentation <a href="http://www.boost.org/doc/libs/1_51_0/libs/python/doc/v2/class.html" rel="nofollow">here</a>, I figured that the problem is that the callback class is the real class being wrapped by Boost.Python, and that it has to be a concrete class. So I implemented in it the missing pure virtual methods:</p> <pre><code>class VAlgorithm_callback: public VAlgorithm { public: VAlgorithm_callback(PyObject *p, const char *name) : self(p), VAlgorithm(name) { } virtual bool Initialize() { return call_method&lt;bool&gt;(self, "Initialize"); } virtual bool Process() { return call_method&lt;bool&gt;(self, "Process"); } virtual bool Finalize() { return call_method&lt;bool&gt;(self, "Finalize"); } const char * GetName() const { return call_method&lt;const char *&gt;(self, "GetName"); } // Supplies the default implementation of GetName static const char * GetName_default(const VAlgorithm&amp; self_) { return self_.VAlgorithm::GetName(); } private: PyObject *self; }; </code></pre> <p>and also modified the wrapper as:</p> <pre><code>class_&lt;VAlgorithm, boost::shared_ptr&lt;VAlgorithm_callback&gt;, boost::noncopyable ("VAlgorithm", init&lt;const char *&gt;()) // .def("Initialize", &amp;VAlgorithm_callback::Initialize) .def("Process", &amp;VAlgorithm_callback::Process) .def("Finalize", &amp;VAlgorithm_callback::Finalize) .def("GetName", &amp;VAlgorithm_callback::GetName_default); </code></pre> <p>Now I can define a child class in Python and call the default GetName() method:</p> <pre><code>&gt;&gt;&gt; class ConcAlg(VAlgorithm): ... pass ... &gt;&gt;&gt; c = ConcAlg("c") &gt;&gt;&gt; c.GetName() 'c' &gt;&gt;&gt; </code></pre>
 

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