Python function issue

Question

Hi i am a beginner who is learning Python, i have stumbled across this example in a book and for some reason when i attempt the same code myself i am not receiving the same output? Please help...

def tester(start):
    state = start
    def nested(label):
        nonlocal state
        print(label, state)
        state += 1
    return nested

>>> F = tester(0)
>>> F('spam')
spam 0
>>> F('ham')
ham 1
>>> F('eggs')
eggs 2

My results are not incrementing + 1 each time i run the function, is there something wrong with the book?

@Keith it doesn't work at all in Python 2.x (throws error at `nonlocal state`). Anyway I tried it in terminal, it works fine to me. — Nadir Sampaoli, Jun 11 '12 at 10:47

score 1 · Accepted Answer · answered Jun 11 '12 at 10:45

1

Works for me. Are you sure you're using python 3? nonlocal is a python 3 feature, and will not work in python 2.x.

answered Jun 11 '12 at 10:45

Eric

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How do you know if you are using python 3? i just run python interactively in my terminal by typing 'python'? or do you need to run it differently for python 3? i do have python 3.2 installed. – thechrishaddad Jun 11 '12 at 10:50
@user1265535: When you open up your Python Terminal, the first line has the version listed for eg. `Python 2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 bit (Intel)] on win32` – Christian Witts Jun 11 '12 at 10:51
yeah okay my bad it works in terminal now which is weird Thanks :) – thechrishaddad Jun 11 '12 at 10:55

score 0 · Answer 2 · edited May 23 '17 at 10:24

0

https://stackoverflow.com/a/1261961/778858 sums it up. Basically python changed a lot from 2.~ to 3.0 >= and you end up with issues like this. Compare what it says at the start of the book with the version they are using and compare it to your own.

edited May 23 '17 at 10:24

Community

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answered Jun 11 '12 at 10:45

jett

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Python function issue

2 Answers2