检查PyObject是否为None [英] Check if PyObject is None

问题描述

我只想检查一下 PyObject 是否为 None 。我天真地期望从函数返回的任何无 Pyobject * 将是一个NULL指针，但是似乎

I would just like to check if a PyObject that I have is None. I naively expected that any None Pyobject * returned from a function would be a NULL pointer, but that doesn't seem to be the case.

所以：如何检查我的 PyObject * 是否指向无对象？

So: how do I check if a PyObject * of mine points to a None object?

我知道有像 PyInt_Check（PyObject *），但我找不到像 PyNone_Check 。我想我可以检查我的 PyObject 和 Py_None 之间的平等，但结果是我甚至不知道

I know that there are macros like PyInt_Check(PyObject *) around, but I couldn't find anything like PyNone_Check. I thought I could just check the equality between my PyObject and Py_None, but turns out I don't even know how to make equality comparisons with this library.

推荐答案

您可以直接与 Py_None 使用 == ：

if (obj == Py_None)

从 docs ：

注意 PyTypeObject 无不直接暴露在
Python / C API中。 由于 None 是一个单例，测试对象标识
（使用C中的 == 对于
没有 PyNone_Check（）函数同样的原因。

Note that the PyTypeObject for None is not directly exposed in the Python/C API. Since None is a singleton, testing for object identity (using == in C) is sufficient. There is no PyNone_Check() function for the same reason.

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