[docs] [issue21785] __getitem__ and __setitem__ try to be smart when invoked with negative slice indices
report at bugs.python.org
Tue Jun 17 09:54:58 CEST 2014
Konstantin Tretyakov added the comment:
Do note that things are not as simple as "slices with negative indices are treated differently from scalar negative indicies".
Namely, behaviour differs whether you use  or .__getitem__, and whether you use [a:b] or [slice(a,b)]. This does not make sense from a specification perspective, but has to be made clear in the docs then.
Besides, Jython does not have this problem and I presume other Python implementations might also be fine (e.g. PyPy or whatever else there exists, couldn't test now).
Hence, although fixing the docs does seem like a simple solution, if you want to regard the docs as a "specification of the Python language" rather than a list of particular CPython features, this won't be reasonable.
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