Python C扩展中的True * args和** kwargs

True *args and **kwargs in Python C extension

我正在开发python 3 c扩展。

我可以得到等价的或任意的位置或关键字参数吗？

例如，在python中，我可以写：

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def fun(name, parent, *args, **kwargs):
# do something with name and parent
# do something with args and kwargs
pass

但是我在C语言中找不到一个简单的等价物。虽然我们可以用PyObject* args和PyObject* kwargs完美地编写函数，但我不能轻易地"解析"名称和父级，无论它来自哪个(args/kwargs)。

采取：

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static PyObject* myFunction(PyObject* self, PyObject* args, PyObject* kwargs) {
char* kwds[] = {"parent","name", NULL};
PyObject* name = NULL;
PyObject* parent = NULL;
if (!PyArg_ParseTupleAndKeywords(args, kwargs,"OO", kwds, &parent, &name)) {
goto errorParseTupleAndKeywords;
}
/* Do something with name and parent */
/* parent and name maybe have appeared either in args or kwargs */
/* But I don't have any extra positional (*args) or keyword (**kwargs) here */
}

号

我能想到的"手动"方法大致如下：

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static PyObject* myFunction(PyObject* self, PyObject* args, PyObject* kwargs) {
PyObject* name = NULL;
PyObject* parent = NULL;
int inKwargs = 0;
// Pretend to do something with parent
if (PyDict_GetItemString(kwargs,"parent")) {
inKwargs++;
PyDict_DelItemString(kwargs,"parent");
}
// Pretend to do something with name
if (PyDict_GetItemString(kwargs,"name")) {
inKwargs++;
PyDict_DelItemString(kwargs,"name");
}
// Not sure if -1 works here
PyObject* newArgs = PyTuple_GetSlice(args, inKwargs, -1); // this is *args
// the remaining kwargs can be used as **kwargs
}