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

Guido van Rossum guido at python.org
Mon Mar 19 23:04:52 CET 2012

On Mon, Mar 19, 2012 at 2:58 PM, Peter Moody <pmoody at google.com> wrote:

On Mon, Mar 19, 2012 at 12:55 PM, Guido van Rossum <guido at python.org> wrote:

On Mon, Mar 19, 2012 at 12:37 PM, Ethan Furman <ethan at stoneleaf.us> wrote:

Nick Coghlan wrote:

Collapsing the address list has to build the result list anyway to actually handle the deduplication part of its job, so returning a concrete list makes sense in that case.

Having only one function return a list instead of an iterator seems questionable. Depending on the code it could either keep track of what it has returned so far in a set and avoid duplication that way; or, just return an iter(listobject) instead of listobject. I know I'm lacking context, but is the list ever expected to be huge? If not, what's wrong with always returning a list? It's possible to return massive lists, (eg, returning the 4+ billion /128 subnets in /96 or something even larger, but I don't think that's very common). I've generally tried to avoid confusion by having 'iter' in the iterating methods, but if more of the methods return iterators, maybe I need to rethink that?

I personally like having 'iter' in the name (e.g. iterkeys() -- note that we dropped this in Py3k because it's no longer an iterator, it's a dict view now. But I don't want to promote that style for ipaddr.py.

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

More information about the Python-Dev mailing list