Merged revisions 53875-53911 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r53899 | neal.norwitz | 2007-02-25 16:52:27 +0100 (Sun, 25 Feb 2007) | 1 line

  Add more details when releasing interned strings
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  r53900 | neal.norwitz | 2007-02-25 16:53:36 +0100 (Sun, 25 Feb 2007) | 1 line

  Whitespace only changes
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  r53901 | jeremy.hylton | 2007-02-25 16:57:45 +0100 (Sun, 25 Feb 2007) | 8 lines

  Fix crash in exec when unicode filename can't be decoded.

  I can't think of an easy way to test this behavior.  It only occurs
  when the file system default encoding and the interpreter default
  encoding are different, such that you can open the file but not decode
  its name.
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  r53902 | jeremy.hylton | 2007-02-25 17:01:58 +0100 (Sun, 25 Feb 2007) | 2 lines

  Put declarations before code.
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  r53910 | fred.drake | 2007-02-25 18:56:27 +0100 (Sun, 25 Feb 2007) | 3 lines

  - SF patch #1657613: add documentation for the Element interface
  - clean up bogus use of the {datadescni} environment everywhere
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  r53911 | neal.norwitz | 2007-02-25 20:44:48 +0100 (Sun, 25 Feb 2007) | 17 lines

  Variation of patch # 1624059 to speed up checking if an object is a subclass
  of some of the common builtin types.

  Use a bit in tp_flags for each common builtin type.  Check the bit
  to determine if any instance is a subclass of these common types.
  The check avoids a function call and O(n) search of the base classes.
  The check is done in the various Py*_Check macros rather than calling
  PyType_IsSubtype().

  All the bits are set in tp_flags when the type is declared
  in the Objects/*object.c files because PyType_Ready() is not called
  for all the types.  Should PyType_Ready() be called for all types?
  If so and the change is made, the changes to the Objects/*object.c files
  can be reverted (remove setting the tp_flags).  Objects/typeobject.c
  would also have to be modified to add conditions
  for Py*_CheckExact() in addition to each the PyType_IsSubtype check.
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Include/unicodeobject.h

@@ -392,7 +392,8 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyUnicode_Type;
 
-#define PyUnicode_Check(op) PyObject_TypeCheck(op, &PyUnicode_Type)
+#define PyUnicode_Check(op) \
+                 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_UNICODE_SUBCLASS)
 #define PyUnicode_CheckExact(op) ((op)->ob_type == &PyUnicode_Type)
 
 /* Fast access macros */