2019-05-17 11:55:34 +02:00
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.. highlight:: c
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2008-01-20 09:30:57 +00:00
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.. _noneobject:
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2016-10-19 16:29:26 +03:00
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The ``None`` Object
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-------------------
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2008-01-20 09:30:57 +00:00
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.. index:: object: None
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2010-10-06 10:11:56 +00:00
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Note that the :c:type:`PyTypeObject` for ``None`` is not directly exposed in the
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2008-01-20 09:30:57 +00:00
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Python/C API. Since ``None`` is a singleton, testing for object identity (using
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2010-10-06 10:11:56 +00:00
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``==`` in C) is sufficient. There is no :c:func:`PyNone_Check` function for the
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2008-01-20 09:30:57 +00:00
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same reason.
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2010-10-06 10:11:56 +00:00
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.. c:var:: PyObject* Py_None
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2008-01-20 09:30:57 +00:00
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The Python ``None`` object, denoting lack of value. This object has no methods.
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It needs to be treated just like any other object with respect to reference
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counts.
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2010-10-06 10:11:56 +00:00
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.. c:macro:: Py_RETURN_NONE
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2008-01-20 09:30:57 +00:00
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2010-10-06 10:11:56 +00:00
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Properly handle returning :c:data:`Py_None` from within a C function (that is,
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2016-10-19 16:29:26 +03:00
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increment the reference count of ``None`` and return it.)
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