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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In C++, it's an error to pass a string literal to a char* function
without a const_cast().  Rather than require every C++ extension
module to put a cast around string literals, fix the API to state the
const-ness.

I focused on parts of the API where people usually pass literals:
PyArg_ParseTuple() and friends, Py_BuildValue(), PyMethodDef, the type
slots, etc.  Predictably, there were a large set of functions that
needed to be fixed as a result of these changes.  The most pervasive
change was to make the keyword args list passed to
PyArg_ParseTupleAndKewords() to be a const char *kwlist[].

One cast was required as a result of the changes:  A type object
mallocs the memory for its tp_doc slot and later frees it.
PyTypeObject says that tp_doc is const char *; but if the type was
created by type_new(), we know it is safe to cast to char *.

Gernot Hillier added more detail to the internal API documentation.

Don't pollute the namespace when protecting against multiple header inclusion.
Prefix with Py_ and use standard naming convention Py_FILENAME_H.

xxxPyCObject_Import() seems to be a copy of PyCObject_Import().

permission from Paul Everitt).  Also removed a few other references to
Digital Creations and changed the remaining ones to Zope Corporation.