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Python Python Basics (Retired) Putting the "Fun" Back in "Function" Shopping List Redux

Posted by Leila Loezer
Leila Loezer
4,869 Points

Empty shopping list items

When this code is running, if I press "enter" without inputting any text the code still adds an item to the list, so I have an empty or null item. What would be the best way to prevent creating these empty items? This is the part of the code for the new_item input:

while True: new_item = input("> ")

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

One way to reject empty input would be to check if input is the empty string then continue the loop for the next input:

while True:
    new_item = input("> ")
    if new_item == "":
        continue

    # remain input processing code here
Kenneth Love
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher 
if new_item:

should be sufficient. An empty string is false-y.