python 3 iterator not executing next

Question

Why does an iterator in python 3 support __next__ and not next? Is it not supposed to be called directly but only while doing :

 for i in iterator:
      dosomething(i)

I have a use case where I would like to call next. For example using itertools.count for a stream of increasing integers. I would like to do :

from itertools import count
    cnt = count(0)
    one(cnt.next())
    two(cnt.next())

Right now I can do the above by using __next__ which suggests to me that it is supposed to not be called externally?

score 3 · Accepted Answer · answered Oct 16 '14 at 20:24

3

In Python 3, use the global function next():

one(next(cnt))

answered Oct 16 '14 at 20:24

Greg Hewgill

@khelwood Well, 2.6+, but those who don't even have that face bigger problems than their iterator fu not being forward compatible. – Oct 16 '14 at 20:26

1 Answers1