Normally, you use itertools.zip_longest
for this:
>>> import itertools
>>> a = [1, 2, 3]
>>> b = [9, 10]
>>> for i in itertools.zip_longest(a, b): print(i)
...
(1, 9)
(2, 10)
(3, None)
But zip_longest
pads the shorter iterable with None
s (or whatever value you pass as the fillvalue=
parameter). If that’s not what you want then you can use a comprehension to filter out the None
s:
>>> for i in (tuple(p for p in pair if p is not None)
... for pair in itertools.zip_longest(a, b)):
... print(i)
...
(1, 9)
(2, 10)
(3,)
but note that if either of the iterables has None
values, this will filter them out too. If you don’t want that, define your own object for fillvalue=
and filter that instead of None
:
sentinel = object()
def zip_longest_no_fill(a, b):
for i in itertools.zip_longest(a, b, fillvalue=sentinel):
yield tuple(x for x in i if x is not sentinel)
list(zip_longest_no_fill(a, b)) # [(1, 9), (2, 10), (3,)]