[Python-Dev] PEP czar for PEP 3144? (original) (raw)

Guido van Rossum guido at python.org
Tue Mar 20 00:34:17 CET 2012

On Mon, Mar 19, 2012 at 3:44 PM, Terry Reedy <tjreedy at udel.edu> wrote:

I am not sure which way you are pointing, but the general default in 3.x is to return iterators: range, zip, enumerate, map, filter, reversed, open (file objects), as well at the dict methods.

Actually as I tried to say, the dict methods (keys() etc.) DON'T return iterators. They return "views" which are iterable.

Anyway, I also tried to imply that it matters if the number of list items would ever be huge. It seems that is indeed possible (even if not likely) so I think iterators are useful.

I am quite happy to be rid of the 'iter' prefix on the latter. This is aside from itertools. The main exceptions I can think of are str.split and sorted. For sorted, a list must be constructed anyway, so might as well return it. This apparently matches the case under consideration. If name differentiation is wanted, call it xxxlist.

Agreed, ideally you don't need to know or it'll be obvious from the name without an explicit 'list' or 'iter'.

-- --Guido van Rossum (python.org/~guido)

More information about the Python-Dev mailing list