Merged revisions 75365,75394,75402-75403,75418,75459,75484,75592-75596,75600,75602-75607,75610-75613,75616-75617,75623,75627,75640,75647,75696,75795 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r75365 | georg.brandl | 2009-10-11 22:16:16 +0200 (So, 11 Okt 2009) | 1 line

  Fix broken links found by "make linkcheck".  scipy.org seems to be done right now, so I could not verify links going there.
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  r75394 | georg.brandl | 2009-10-13 20:10:59 +0200 (Di, 13 Okt 2009) | 1 line

  Fix markup.
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  r75402 | georg.brandl | 2009-10-14 17:51:48 +0200 (Mi, 14 Okt 2009) | 1 line

  #7125: fix typo.
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  r75403 | georg.brandl | 2009-10-14 17:57:46 +0200 (Mi, 14 Okt 2009) | 1 line

  #7126: os.environ changes *do* take effect in subprocesses started with os.system().
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  r75418 | georg.brandl | 2009-10-14 20:48:32 +0200 (Mi, 14 Okt 2009) | 1 line

  #7116: str.join() takes an iterable.
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  r75459 | georg.brandl | 2009-10-17 10:57:43 +0200 (Sa, 17 Okt 2009) | 1 line

  Fix refleaks in _ctypes PyCSimpleType_New, which fixes the refleak seen in test___all__.
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  r75484 | georg.brandl | 2009-10-18 09:58:12 +0200 (So, 18 Okt 2009) | 1 line

  Fix missing word.
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  r75592 | georg.brandl | 2009-10-22 09:05:48 +0200 (Do, 22 Okt 2009) | 1 line

  Fix punctuation.
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  r75593 | georg.brandl | 2009-10-22 09:06:49 +0200 (Do, 22 Okt 2009) | 1 line

  Revert unintended change.
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  r75594 | georg.brandl | 2009-10-22 09:56:02 +0200 (Do, 22 Okt 2009) | 1 line

  Fix markup.
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  r75595 | georg.brandl | 2009-10-22 09:56:56 +0200 (Do, 22 Okt 2009) | 1 line

  Fix duplicate target.
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  r75596 | georg.brandl | 2009-10-22 10:05:04 +0200 (Do, 22 Okt 2009) | 1 line

  Add a new directive marking up implementation details and start using it.
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  r75600 | georg.brandl | 2009-10-22 13:01:46 +0200 (Do, 22 Okt 2009) | 1 line

  Make it more robust.
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  r75602 | georg.brandl | 2009-10-22 13:28:06 +0200 (Do, 22 Okt 2009) | 1 line

  Document new directive.
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  r75603 | georg.brandl | 2009-10-22 13:28:23 +0200 (Do, 22 Okt 2009) | 1 line

  Allow short form with text as argument.
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  r75604 | georg.brandl | 2009-10-22 13:36:50 +0200 (Do, 22 Okt 2009) | 1 line

  Fix stylesheet for multi-paragraph impl-details.
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  r75605 | georg.brandl | 2009-10-22 13:48:10 +0200 (Do, 22 Okt 2009) | 1 line

  Use "impl-detail" directive where applicable.
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  r75606 | georg.brandl | 2009-10-22 17:00:06 +0200 (Do, 22 Okt 2009) | 1 line

  #6324: membership test tries iteration via __iter__.
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  r75607 | georg.brandl | 2009-10-22 17:04:09 +0200 (Do, 22 Okt 2009) | 1 line

  #7088: document new functions in signal as Unix-only.
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  r75610 | georg.brandl | 2009-10-22 17:27:24 +0200 (Do, 22 Okt 2009) | 1 line

  Reorder __slots__ fine print and add a clarification.
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  r75611 | georg.brandl | 2009-10-22 17:42:32 +0200 (Do, 22 Okt 2009) | 1 line

  #7035: improve docs of the various <method>_errors() functions, and give them docstrings.
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  r75612 | georg.brandl | 2009-10-22 17:52:15 +0200 (Do, 22 Okt 2009) | 1 line

  #7156: document curses as Unix-only.
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  r75613 | georg.brandl | 2009-10-22 17:54:35 +0200 (Do, 22 Okt 2009) | 1 line

  #6977: getopt does not support optional option arguments.
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  r75616 | georg.brandl | 2009-10-22 18:17:05 +0200 (Do, 22 Okt 2009) | 1 line

  Add proper references.
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  r75617 | georg.brandl | 2009-10-22 18:20:55 +0200 (Do, 22 Okt 2009) | 1 line

  Make printout margin important.
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  r75623 | georg.brandl | 2009-10-23 10:14:44 +0200 (Fr, 23 Okt 2009) | 1 line

  #7188: fix optionxform() docs.
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  r75627 | fred.drake | 2009-10-23 15:04:51 +0200 (Fr, 23 Okt 2009) | 2 lines

  add further note about what's passed to optionxform
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  r75640 | neil.schemenauer | 2009-10-23 21:58:17 +0200 (Fr, 23 Okt 2009) | 2 lines

  Improve some docstrings in the 'warnings' module.
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  r75647 | georg.brandl | 2009-10-24 12:04:19 +0200 (Sa, 24 Okt 2009) | 1 line

  Fix markup.
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  r75696 | georg.brandl | 2009-10-25 21:25:43 +0100 (So, 25 Okt 2009) | 1 line

  Fix a demo.
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  r75795 | georg.brandl | 2009-10-27 16:10:22 +0100 (Di, 27 Okt 2009) | 1 line

  Fix a strange mis-edit.
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diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst
index 971c06e..36fc575 100644
--- a/Doc/reference/datamodel.rst
+++ b/Doc/reference/datamodel.rst
@@ -59,13 +59,16 @@
 they may be garbage-collected.  An implementation is allowed to postpone garbage
 collection or omit it altogether --- it is a matter of implementation quality
 how garbage collection is implemented, as long as no objects are collected that
-are still reachable.  (Implementation note: CPython currently uses a
-reference-counting scheme with (optional) delayed detection of cyclically linked
-garbage, which collects most objects as soon as they become unreachable, but is
-not guaranteed to collect garbage containing circular references.  See the
-documentation of the :mod:`gc` module for information on controlling the
-collection of cyclic garbage.  Other implementations act differently and CPython
-may change.)
+are still reachable.
+
+.. impl-detail::
+
+   CPython currently uses a reference-counting scheme with (optional) delayed
+   detection of cyclically linked garbage, which collects most objects as soon
+   as they become unreachable, but is not guaranteed to collect garbage
+   containing circular references.  See the documentation of the :mod:`gc`
+   module for information on controlling the collection of cyclic garbage.
+   Other implementations act differently and CPython may change.
 
 Note that the use of the implementation's tracing or debugging facilities may
 keep objects alive that would normally be collectable. Also note that catching
@@ -1469,15 +1472,15 @@
   *__slots__*; otherwise, the class attribute would overwrite the descriptor
   assignment.
 
+* The action of a *__slots__* declaration is limited to the class where it is
+  defined.  As a result, subclasses will have a *__dict__* unless they also define
+  *__slots__* (which must only contain names of any *additional* slots).
+
 * If a class defines a slot also defined in a base class, the instance variable
   defined by the base class slot is inaccessible (except by retrieving its
   descriptor directly from the base class). This renders the meaning of the
   program undefined.  In the future, a check may be added to prevent this.
 
-* The action of a *__slots__* declaration is limited to the class where it is
-  defined.  As a result, subclasses will have a *__dict__* unless they also define
-  *__slots__*.
-
 * Nonempty *__slots__* does not work for classes derived from "variable-length"
   built-in types such as :class:`int`, :class:`str` and :class:`tuple`.
 
@@ -1714,12 +1717,16 @@
 supply the following special method with a more efficient implementation, which
 also does not require the object be a sequence.
 
-
 .. method:: object.__contains__(self, item)
 
-   Called to implement membership test operators.  Should return true if *item* is
-   in *self*, false otherwise.  For mapping objects, this should consider the keys
-   of the mapping rather than the values or the key-item pairs.
+   Called to implement membership test operators.  Should return true if *item*
+   is in *self*, false otherwise.  For mapping objects, this should consider the
+   keys of the mapping rather than the values or the key-item pairs.
+
+   For objects that don't define :meth:`__contains__`, the membership test first
+   tries iteration via :meth:`__iter__`, then the old sequence iteration
+   protocol via :meth:`__getitem__`, see :ref:`this section in the language
+   reference <membership-test-details>`.
 
 
 .. _numeric-types: