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

[Adam DePrince]

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. 

- Adam