symbian-qemu-0.9.1-12/python-2.6.1/Doc/c-api/none.rst
author martin.trojer@nokia.com
Fri, 31 Jul 2009 15:01:17 +0100
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.. highlightlang:: c
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.. _noneobject:
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The None Object
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---------------
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.. index:: object: None
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Note that the :ctype:`PyTypeObject` for ``None`` is not directly exposed in the
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Python/C API.  Since ``None`` is a singleton, testing for object identity (using
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``==`` in C) is sufficient. There is no :cfunc:`PyNone_Check` function for the
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same reason.
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.. cvar:: PyObject* Py_None
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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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.. cmacro:: Py_RETURN_NONE
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   Properly handle returning :cdata:`Py_None` from within a C function.
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   .. versionadded:: 2.4
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