symbian-qemu-0.9.1-12/python-2.6.1/Doc/c-api/none.rst
author Gareth Stockwell <gareth.stockwell@accenture.com>
Wed, 22 Sep 2010 15:40:40 +0100
branchgraphics-phase-3
changeset 111 345f1c88c950
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Fixes to syborg-graphicswrapper.vcproj These changes allow syborg-graphicswrapper to link against the hostthreadadapter and khronosapiwrapper libraries built by the graphics.simulator component. The .vcproj file uses relative paths, which requires that the following three packages are laid out as follows: os/ graphics adapt/ graphics.simulator qemu
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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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