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

Ethan Furman ethan at stoneleaf.us
Mon Mar 19 21:13:56 CET 2012

Guido van Rossum 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?

Nothing wrong in and of itself. It just seems to me that if we have several functions that deal with ip addresses/networks/etc, and all but one return iterators, that one is going to be a pain... 'Which one returns a list again? Oh yeah, that one.'

Granted it's mostly a stylistic preference for consistency.

Ethan

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