[Python-Dev] PEP 322: Reverse Iteration
Guido van Rossum
guido at python.org
Tue Nov 4 19:07:40 EST 2003
> > > for i, value in reversed(enumerate(listofnum)):
> > Sorry, this doesn't work. enumerate() returns an iterator, reversed()
> > requires a sequence.
> I believe the assumption is that enumerate (as well as the proposed irange)
> would grow an __reversed__ method to handle just that usage.
Ah, so it is. Then the PEP's abstract is wrong:
This proposal is to add a builtin function to support reverse
iteration over sequences.
Also, the PEP should enumerate (:-) which built-in types should be
modified in this way, to give an impression of the enormity (or not)
of the task.
--Guido van Rossum (home page: http://www.python.org/~guido/)
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