for loop and a list.remove() doesn't remove all the items in the list in python

Question

names_friends=["Juan","Efren","Kiki", "Esmoris", "Diego", "Nando"]
for i in names_friends:
    print(i)
    names_friends.remove(i)

print(names_friends)

After run this code I got this.

Juan
Kiki
Diego
['Efren', 'Esmoris', 'Nando']

I would highly appreciate if someone could explain to me why it doesn't remove all the items of the list.Thanks

Its really not a good idea to change a list while iterating over it — rafaelc, Jul 30 '18 at 23:51
try https://stackoverflow.com/questions/1207406/how-to-remove-items-from-a-list-while-iterating — Paul Rooney, Jul 30 '18 at 23:51

rafaelc · Answer 1 · 2018-07-31T00:14:11.350

2

You are changing the iterable while iterating over it. So once you delete a object from it, it may skip the next one.

If you iterate over a copy, this problem goes away, e.g.

for i in names_friends[:]:
    print(i)
    names_friends.remove(i)

edited Jul 31 '18 at 00:14

answered Jul 30 '18 at 23:53

rafaelc

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for loop and a list.remove() doesn't remove all the items in the list in python

1 Answers1