Jacques Gaudin Jacques Gaudin - 7 months ago 56
Python Question

zip in IronPython 2.7 and Python3.5

I have a script that I want to execute both in Python3.5 and IronPython2.7.

The script is originally written with Python3 in mind, so I have some nested loops similar to the code below :

myIter0 = iter(['foo','foo','bar','foo','spam','spam'])
myIter1 = iter(['foo','bar','spam','foo','spam','bar'])
myIter2 = iter([1,2,3,4,5,6])

for a in myIter0:
for b, c in zip(myIter1, myIter2):
if a + b == 'foobar':
print(c)
break


Now if I run this in IronPython2.7 I don't get the same result because zip returns a list and not an iterator.

To circumvent this problem, I thought I would do :

import sys
if sys.version_info.major == 2:
from itertools import izip as _zip
else:
_zip = zip

myIter0 = iter(['foo','foo','bar','foo','spam','spam'])
myIter1 = iter(['foo','bar','spam','foo','spam','bar'])
myIter2 = iter([1,2,3,4,5,6])

for a in myIter0:
for b, c in _zip(myIter1, myIter2):
if a + b == 'foobar':
print(c)
break


Is there any better way to do this ?

Answer

You can use builtins from the future lib.

from builtins import zip

In python2 you get an itertools.izip and in python3 you just get zip.

In [1]: from builtins import zip

In [2]: zip([1,2,3,4])
Out[2]: <itertools.izip at 0x7fa16c8496c8>

In [1]: from builtins import zip

In [2]: zip([1,2,3,4])
Out[2]: <zip at 0x7f13dfb9c188>