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Python Python Collections (2016, retired 2019) Lists Disemvowel

Posted by newpal
newpal
1,717 Points

what is wrong with my code?

def disemvowel(word): word_list = list(word) for letter in word_list: if letter in ["A", "a", "E", "e", "I", "i", "O", "o", "U", "u"]: word_list.remove(letter) word_string = ''.join(word_list) return word_string

disemvowel.py 
def disemvowel(word):
    word_list = list(word)
    for letter in word_list:
        if letter in ["A", "a", "E", "e", "I", "i", "O", "o", "U", "u"]:
            word_list.remove(letter)
    word_string = ''.join(word_list)
    return word_string

3 Answers

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

When you alter an iterable while it is being used to control a loop, it can cause items to be skipped over. One way to avoid this is to iterate using a copy of the iterable.

Alexander Davison
Alexander Davison
65,469 Points

Or you could simply iterate on the original string word instead :wink:

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

That would work in this case, but it's not a good practice in case the number or order of items got changed in the conversion process.

Alexander Davison
Alexander Davison
65,469 Points

True.

newpal
newpal
1,717 Points
newpal
newpal
1,717 Points

Thank you Steven and Alexander for your answers! I tried using the original string word, but then I could not use the remove() method in the if statement.

Steven, Could you please explain how to use a copy of the iterable to solve this question?

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points 
    for letter in word_list.copy():   # or...
    for letter in word_list[:]:       # an unlimited slice is also a copy
newpal
newpal
1,717 Points
newpal
newpal
1,717 Points

Thank you Steven for your help! Much appreciated!