We should be reading the source: https://github.com/python/cpython/blob/master/Objects/dictobject.c AFAIU, direct subscripting / addressing was not a use case in the design phase of the current dict? Could a __getitem__(slice_or_int_index) be implemented which just skips over the NULLs? Or would that be no faster than or exactly what islice does when next()'ing through? On Fri, Jul 31, 2020 at 9:14 PM Inada Naoki <songofacandy@gmail.com> wrote:
On Sat, Aug 1, 2020 at 10:04 AM Wes Turner <wes.turner@gmail.com> wrote:
Actually, I think the reverse traversal case is the worst case because:
it's not possible to use negative subscripts with islice (because that would require making a full copy).
This doesn't work:
islice(dict.keys(), -1, -5)
Reverse traversal did work in Python 2 but was foregone when making
.keys() a view in Python 3 in order to avoid lulling users into making usually unnecessary copies.
dict is reversible now. You can do `islice(dict, 0, 5)`.
-- Inada Naoki <songofacandy@gmail.com>