Avoid repetition of loop body before loop

Question

Ws you can see below, the code above and under the start of loop looks pretty much same. Is it possible to avoid this repetition?

Code:

term = ","
file_name = input("What is the file name? ")
f_extns = file_name.split(".")  #splitting file extension from file name
while term in file_name:
     print("Please type file name again with . not, ")
     file_name = input("What is the file name? ")
     f_extns = file_name.split(".")
else:
    print("The file extension is: " + repr(f_extns[-1]))

Does this answer your question? [Asking the user for input until they give a valid response](https://stackoverflow.com/questions/23294658/asking-the-user-for-input-until-they-give-a-valid-response) See the [top answer](https://stackoverflow.com/a/23294659/4518341) under **Implementing Your Own Validation Rules** — wjandrea, Jul 05 '20 at 20:36
Yeah, you can do it. Create a function that has the code in it, and just call it when you need. — alfadog67, Jul 08 '20 at 16:43

Brian61354270 · Answer 1 · 2020-07-05T20:39:36.130

2

You could use an infinite loop and only break when the exit condition is met.

while True:
    file_name = input("What is the file name? ")
    f_extns = file_name.split(".")

    if term not in file_name:
        break
    else:
        print("Please type file name again with . not, ")

edited Jul 05 '20 at 20:39

answered Jul 05 '20 at 20:37

Brian61354270

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Oh this is much smarter – Shrey Jul 05 '20 at 20:39
1

The `else` statement isn't necessary. – Red Jul 05 '20 at 20:40
@AnnZen Quite true, but I generally lean towards including it to make the separation of the branches clearer. – Brian61354270 Jul 05 '20 at 20:43

score 0 · Accepted Answer · answered Jul 05 '20 at 20:38

Like this:

term = ","
while True:
    file_name = input("What is the file name? ")
    if term not in file_name: # If the user didn't input any commas
        print("The file extension is: ", file_name.rsplit('.')[0])
        break
    print("Please type file name again with . not, ")

score 0 · Answer 3 · answered Jul 05 '20 at 20:38

You can simplify your code by doing this

term = ","
file_name = input("What is the file name? ")
while term in file_name:
     print("Please type file name again with . not, ")
     file_name = input("What is the file name? ")
f_extns = file_name.split(".")
print("The file extension is: " + repr(f_extns[-1]))

This takes the input and as long as there is a comma in the input it will ask the user to repeat the filename. As soon as they enter a correct file name it will exit the loop and split by period.

Avoid repetition of loop body before loop

3 Answers3