| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 1 | .. highlightlang:: c |
| 2 | |
| 3 | .. _noneobject: |
| 4 | |
| 5 | The None Object |
| 6 | --------------- |
| 7 | |
| 8 | .. index:: object: None |
| 9 | |
| Georg Brandl | 60203b4 | 2010-10-06 10:11:56 +0000 | [diff] [blame] | 10 | Note that the :c:type:`PyTypeObject` for ``None`` is not directly exposed in the |
| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 11 | Python/C API. Since ``None`` is a singleton, testing for object identity (using |
| Georg Brandl | 60203b4 | 2010-10-06 10:11:56 +0000 | [diff] [blame] | 12 | ``==`` in C) is sufficient. There is no :c:func:`PyNone_Check` function for the |
| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 13 | same reason. |
| 14 | |
| 15 | |
| Georg Brandl | 60203b4 | 2010-10-06 10:11:56 +0000 | [diff] [blame] | 16 | .. c:var:: PyObject* Py_None |
| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 17 | |
| 18 | The Python ``None`` object, denoting lack of value. This object has no methods. |
| 19 | It needs to be treated just like any other object with respect to reference |
| 20 | counts. |
| 21 | |
| 22 | |
| Georg Brandl | 60203b4 | 2010-10-06 10:11:56 +0000 | [diff] [blame] | 23 | .. c:macro:: Py_RETURN_NONE |
| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 24 | |
| Georg Brandl | 60203b4 | 2010-10-06 10:11:56 +0000 | [diff] [blame] | 25 | Properly handle returning :c:data:`Py_None` from within a C function (that is, |
| Georg Brandl | 54a3faa | 2008-01-20 09:30:57 +0000 | [diff] [blame] | 26 | increment the reference count of None and return it.) |