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#6034: clarify __reversed__ doc.

This commit is contained in:
Georg Brandl 2009-05-16 11:13:21 +00:00
parent f541378d13
commit 8dc3b445ec
1 changed files with 5 additions and 5 deletions
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Doc/reference/datamodel.rst
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@ -1869,11 +1869,11 @@ sequences, it should iterate through the values.
reverse iteration. It should return a new iterator object that iterates
over all the objects in the container in reverse order.
If the :meth:`__reversed__` method is not provided, the
:func:`reversed` builtin will fall back to using the sequence protocol
(:meth:`__len__` and :meth:`__getitem__`). Objects should normally
only provide :meth:`__reversed__` if they do not support the sequence
protocol and an efficient implementation of reverse iteration is possible.
If the :meth:`__reversed__` method is not provided, the :func:`reversed`
builtin will fall back to using the sequence protocol (:meth:`__len__` and
:meth:`__getitem__`). Objects that support the sequence protocol should
only provide :meth:`__reversed__` if they can provide an implementation
that is more efficient than the one provided by :func:`reversed`.
.. versionadded:: 2.6