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Python Python Collections (Retired) Lists Redux Shopping List Take Three

Posted by R W
R W
19,894 Points

'SHOW' displays nothing

(I wasn't sure how to format code to be indented properly/look okay on the forums so I'm including a screenshot of my code instead.)

I have copied the code from this video line for line into my text editor and when I run it and type 'SHOW' nothing gets displayed. I know a similar question was asked previously-- I tried implementing that code and it threw an error when I tried to call 'SHOW.'

Here is my code: https://w.trhou.se/zt90k1lofz

I've reviewed it several times and cannot figure out what I'm doing incorrectly. I have noticed the code works fine if I remove everything from the 'else' statement apart from the line that appends a new item to the list, so I'm guessing that's where my problem is, I just can't seem to find it.

Any insight would be greatly appreciated!

2 Answers

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

I forked your Workspace and noticed that the indentation for the else statement at the end was lined up under the for loop. What happens, as far as I could tell, is that after you entered a list and just hit enter (meaning don't set an index) then a list would not be created. If you set an index for the list it would double the list regardless of the number entered.

After I fixed the indentation the program ran as expected.

Here is my output after lining up the else statement with the if above it:

treehouse:~/workspace$ python shopping_list.py                                                                 
What do you want to shop for?                                                                                  

Separate each item with a comma.                                                                               
Type DONE to quit, SHOW to see the current list, and HELP to see this message.                                 
> A, B                                                                                                         
Add item at certain spot? Press enter for end of list, or give me a number. Currently 0 items in the list0     
> SHOW                                                                                                         
1: B                                                                                                           
2: A                                                                                                           
> C                                                                                                            
Add item at certain spot? Press enter for end of list, or give me a number. Currently 2 items in the list2     
> SHOW                                                                                                         
1: B                                                                                                           
2: C                                                                                                           
3: A                                                                                                           
> DONE                                                                                                         

Here is your list:                                                                                             
1: B                                                                                                           
2: C                                                                                                           
3: A                                                                                                           
treehouse:~/workspace$
R W
R W
19,894 Points
R W
R W
19,894 Points

Aha! That did it, thank you so much! It really helps to have someone 'proofread' your code (though I should probably wear my glasses while coding as well, maybe I would've spotted that).

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

Heheh. :-p

True. Another set of eyes sometimes helps a ton.