我想从C ++(Base)导出一个抽象类,以在Python(Derived)中创建一个继承的类,最后提取该类以创建一个C ++指针对象(Base *)。我发现this solution.,尽管它可以编译,但对我不起作用,执行异常停止。我的代码是这样的:
#if PY_MAJOR_VERSION >= 3
# define INIT_MODULE PyInit_module
extern "C" PyObject* INIT_MODULE();
#else
# define INIT_MODULE initmodule
extern "C" void INIT_MODULE();
#endif
int main()
{
PyImport_AppendInittab((char*)"module", INIT_MODULE);
Py_Initialize();
object main = import("__main__");
object global = main.attr("__dict__");
PySys_SetPath(L".");
global["derivedmodule"] = import("derivedmodule");
object obj = eval("derivedmodule.Derived()", global);
extract<Base*> ex(obj); // Here is the problem, the extraction didn't work
// { <boost::python::converter::extract_pointer<module::Base*>> =
// {m_source = 0x7ffff6f94030,
// m_result = 0x0}, <No data fields>}
if(ex.check()){
Base * const b = ex();
b->foo();
std::cout << "SUCCESS\n";
return 0;
} else {
std::cout << "FAIL\n"; // Always jumps here.
return 1;
}
}
“” module“和” derivedmodule“在python解释器上工作。
我终于找到了解决方案。在“ derivedmodule”中,类必须像这样初始化基类:
class Derived(derivedmodule.Base):
def __init__(self):
derivedmodule.Base.__init__(self)
并且导入的基类必须具有这样的init函数:
class_<BaseWrap, /*Holder*/, boost::noncopyable>("Base", init<>())
// The holder could be empty or a class like shared_ptr<Base>, but the essential is the init<>() function.