[Python-Dev] Re: Single- vs. Multi-pass iterability

[Guido van Rossum]

> Do you intend to have a test for "is this an iterator" at all?

Not right now, see the rest of my email.  The best you can do is check
for a next method and hope for the best.

> If LBYL is bad, what is introspection good for?

Ask Alex.

> I understand that that's always been "the Python way". However,
> isn't there also some implication that some of the special functions
> are more than just a way to provide implementations of Python's
> syntax?

Like what?

> Notes in the docs like those on __getitem__ tend to argue
> for that, at least by convention.  Unless I'm misinterpreting
> things, "the Python way" isn't quite so one-sided where protocols
> are concerned.

Can you quote specific places in the docs you read this way?  I don't
see it, but I've only scanned chapter 3 of the Language Reference
Manual.

> Just for the record, I never meant to imply that it was broken, only
> that I'd like to get a little more from it than I currently can.

Maybe I should read Ping's email.  From the discussion I figured he
was arguing this way.  I think you have to settle with what I proposed
at the top.

--Guido van Rossum (home page: http://www.python.org/~guido/)