[Python-3000] Iterators for dict keys, values, and items == annoying :) (original) (raw)

Adam DePrince adam.deprince at gmail.com
Sat Apr 1 05:03:39 CEST 2006

On Fri, 2006-03-31 at 07:44 +1000, Nick Coghlan wrote:

Adam DePrince wrote: > There seemed to be a concensus in the community on the size of the view > proposal, and I'm reimplementing the PEP to reflect that. But what I > can't resolve is the other anciliary issue: "To list or iter." I'm not > yet ready to resolve that issue. The views don't resolve it either, and > by their nature are biased towards the iter approach. They provide > iter because its light weight to do, but there is no way a light > weight view can provide you with ordering information from an unordered > datastore. Now, as a means of resolving this conflict, I'm open to the > notion of a view implementing both iter and an explicit .list method > to avoid any extra overhead in generating a list from an iter instead of > directly from the dict as we do now.

Umm, the whole point of the views discussion is the realisation that "list or iterator" is a false dichotomy. The correct answer is "new iterable that looks

The false dichotomy is not of my construction; some of the objections that I've received have been of the form:

"""When I say

print dict.items()

with views instead of iters it still won't look like a list! """

Until that debate is resolved it will still taint discussion of any non-lists that dict.items/values might return.

More information about the Python-3000 mailing list