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Re: local variable 'juveniles' referenced before assignment

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On Wed, Jan 13, 2016 at 11:23 PM, Alan Robinson
<arobinson@lordlawson.org.uk> wrote:
> def menu():
>     option = int(input("Please select an option: \n 1: Set Generation 0 Values \n 2: View Generation 0 Values \n 3: Run Model \n 4: Print values"))
>
>     if option == 1:
>         juveniles,adults,seniles = setGen()
>     elif option == 2:
>         displayGen()
>     elif option == 3:
>         runModel(juveniles,adults,seniles)
>     elif option == 4:
>         print(juveniles,adults,seniles)
>     menu()
>

This is a classic use of recursion instead of iteration. When you call
menu() again, you're creating a completely new 'slot' for the new
function; it has its own set of names. Assigning to names in one call
of menu() has no effect on any other call.

Instead, look into the way a while loop works. You'll find that your
code is simpler and clearer, plus your variables will stay set.

ChrisA

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local variable 'juveniles' referenced before assignment Alan Robinson <arobinson@lordlawson.org.uk> - 2016-01-13 04:23 -0800
  Re: local variable 'juveniles' referenced before assignment Chris Angelico <rosuav@gmail.com> - 2016-01-13 23:32 +1100
    Re: local variable 'juveniles' referenced before assignment Alan Robinson <arobinson@lordlawson.org.uk> - 2016-01-13 04:54 -0800
      Re: local variable 'juveniles' referenced before assignment Chris Angelico <rosuav@gmail.com> - 2016-01-14 00:05 +1100
      Re: local variable 'juveniles' referenced before assignment Peter Otten <__peter__@web.de> - 2016-01-13 14:05 +0100
        Re: local variable 'juveniles' referenced before assignment Alan Robinson <arobinson@lordlawson.org.uk> - 2016-01-13 05:22 -0800
          Re: local variable 'juveniles' referenced before assignment Alan Robinson <arobinson@lordlawson.org.uk> - 2016-01-13 05:26 -0800

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