Lennart Regebro wrote:
On Tue, Mar 22, 2011 at 22:12, Steven D'Aprano <st...@pearwood.info> wrote:
The main one that comes to my mind is that other than looping, any time I
want to process dict.items() etc I often need to call list() first.
"Process" no. If you want it to be a list, yes. This is because they
now return generators, which is a massive improvement.
Well, yes, that's what I meant when I said other than looping. (I'm
aware that there are uses for lazy iterators other than for-loops.)
But the improvement is exactly what Anatoly is talking about: it's an
improvement in speed over user convenience. If all you are doing is
iterating over a moderately-sized dictionary, you probably don't care
whether items() etc. returns a list or an iterator. But if you want to
take those items away and do something with them, you need a list, and
that's ever-so-slightly less convenient now than it was.
To be clear, I'm *not* objecting to this state of affairs. I think the
trade-off in this case is the right thing to do. But Anatoly seems to
think that Python3 has generally made the wrong trade-off, and I was
hoping he would mention some other concrete examples.
For the record, this next double-quoted >> statement is not by me. It
was actually from Anatoly Techtonik:
but what I really
didn't expect is to see that choice is made not in user's favor, but
in a favor of speed.
I'm not sure what choice you are talking of here... And in this case
Python 2 behaved differently on different platforms and Python 3
doesn't. That seems to be an improvement to me...
Lennart, please be a little more careful with your attributions.
--
Steven
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