svn+ssh://pythondev@svn.python.org/python/branches/p3yk

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  r56477 | martin.v.loewis | 2007-07-21 09:04:38 +0200 (Sa, 21 Jul 2007) | 11 lines

  Merged revisions 56466-56476 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

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    r56476 | martin.v.loewis | 2007-07-21 08:55:02 +0200 (Sa, 21 Jul 2007) | 4 lines

    PEP 3123: Provide forward compatibility with Python 3.0, while keeping
    backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
    PyVarObject_HEAD_INIT.
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  r56478 | martin.v.loewis | 2007-07-21 09:47:23 +0200 (Sa, 21 Jul 2007) | 2 lines

  PEP 3123: Use proper C inheritance for PyObject.
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  r56479 | martin.v.loewis | 2007-07-21 10:06:55 +0200 (Sa, 21 Jul 2007) | 3 lines

  Add longintrepr.h to Python.h, so that the compiler can
  see that PyFalse is really some kind of PyObject*.
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  r56480 | martin.v.loewis | 2007-07-21 10:47:18 +0200 (Sa, 21 Jul 2007) | 2 lines

  Qualify SHIFT, MASK, BASE.
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  r56482 | martin.v.loewis | 2007-07-21 19:10:57 +0200 (Sa, 21 Jul 2007) | 2 lines

  Correctly refer to _ob_next.
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I banged on the code (beyond what's in that branch) to make fewer tests fail;
the only tests that fail now are:
  test_descr -- can't pickle ints?!
  test_pickletools -- ???
  test_socket -- See python.org/sf/1619659
  test_sqlite -- ???
I'll deal with those later.

Rewrote Py_RETURN_{NONE, TRUE, FALSE} to expand to comma expressions
rather than "do {} while(0)" thingies.  The OP complained because he
likes using MS /W4 sometimes, and then all his uses of these things
generate nuisance warnings about testing a constant expression (in
the "while(0)" part).  Comma expressions don't have this problem
(although it's a lucky accident that comma expressions suffice for these
macros!).

to handle situations like ``if (foo) Py_RETURN_NONE else ...``.

order to prevent any unexpected surprises from someone using them in a
conditional without using curly braces (e.g., ``if (foo) Py_RETURN_TRUE``.

the specified value.  All three Py_INCREF the singleton and then return it.

Thanks to Skip Montanaro and Kalle Svensson for the patches.