Pre-PEP: reverse iteration methods
Hannu Kankaanpää
hanzspam at yahoo.com.au
Wed Sep 24 06:38:11 EDT 2003
Stephen Horne <$$$$$$$$$$$$$$$$$@$$$$$$$$$$$$$$$$$$$$.co.uk> wrote in message news:<f4b2nv8vs81v6egonckq7935jmh6a8gku6 at 4ax.com>...
> >* Should enumerate() be included? It would only provide reverse iteration
> > whenever the underlying sequence supported it.
>
> Why not...
>
> for i, j in enumerate (listname.iter_backwards ()) :
>
> in other words, as enumerate can handle the already-reversed
> sequence/iteration, I don't see the point.
That's not the same:
>>> list(enumerate([10,11,12]))
[(0, 10), (1, 11), (2, 12)]
>>> list(enumerate([10,11,12].riter()))
[(0, 12), (1, 11), (2, 10)]
>>> list(enumerate([10,11,12]).riter())
[(2, 12), (1, 11), (0, 10)]
Indices would also be reversed.
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