itertools.cycle().next()?

Question

Well, I was using itertools.cycle().next() method with Python 2.6.6, but now that I updated to 3.2 I noticed that itertools.cycle() object has no method next().

I used it to cycle a string in the spin()method of a Spinner class. So if we cycle the tuple ('|', '/', '-', '\\', '|', '/', '-'), it'll print: |, /, -, \ , |, /, -, |, / and so on...

I've searched the release notes of Python 3.0, 3.1 and 3.2 and didn't noticed any change on this. When this have changed? Is there any simple alternative to achieve the same functionality as before?

Thank you in advance.

+1 for this funny use case of `cycle` :) – Fred Foo Mar 08 '11 at 20:04 — Fred Foo, Mar 08 '11 at 20:04

score 73 · Accepted Answer · edited May 19 '14 at 07:26

73

iter.next() was removed in python 3. Use next(iter) instead. So in your example change itertools.cycle().next() to next(itertools.cycle())

There is a good example here along with various other porting to python 3 tips. It also compares various other next() idioms in python 2.x vs python 3.x

edited May 19 '14 at 07:26

jeromej

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answered Mar 08 '11 at 20:04

d0ugal

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You answered almost the same thing as @Sven (well, I know, it couldn't be different), but your link saved your answer. I didn't know the http://diveintopython3.org/... Bookmarked! Thanks for the answer and link. :) – Paulo Freitas Mar 08 '11 at 22:42
Yup - we both answered at roughly the same time. Glad you found the link useful, I've found it to be a good reference. – d0ugal Mar 09 '11 at 16:17
Why was `iter.next()` removed? – Kurt Mueller Apr 01 '15 at 02:43
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@KurtMueller A trivial websearch yields the answer: https://www.python.org/dev/peps/pep-3114/ Don't forget to use websearch when you don't know something – David Heffernan Nov 09 '17 at 15:18
The link is dead now. Any chance that anyone can find and update the link? Thanks. – Bowen Liu Nov 15 '19 at 16:41
The link is broken now – Mohammed Shareef C Aug 11 '23 at 06:23

score 17 · Answer 2 · answered Mar 08 '11 at 20:02

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In Python 3.x, iterators don't have it.next() any more. use next(it) instead, which also works in Python 2.6 or above. Internally, this will call it.next() in Python 2.x and it.__next__() in Python 3.x.

answered Mar 08 '11 at 20:02

Sven Marnach

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itertools.cycle().next()?

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