slicing, mapping types, ellipsis etc.
ncoghlan at email.com
Tue Nov 30 14:52:16 CET 2004
Kent Johnson wrote:
> Maybe instead of referring to mappings it should say "The primary must
> implement __getitem__(), which is called with a value that is
> constructed from the slice list, as follows."
In the section you mention, 'mapping' is equivalent to 'has __getitem__
defined', and I'd be surprised if it's an isolated usage. Python actually has
trouble distinguishing between sequences and mappings, as anyone who as tried to
use the 'isMapping' API would know (the isMapping API uses much the same
definition as the reference manual does - so all sequences show up as mappings,
as they map indices and slices to objects).
Section 3 of the reference manual is actually more use for anyone developing
custom types that override special methods. E.g. proper handling of slice
objects is described here under container emulation:
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