try and if - local variable referenced before assignment

Question

I tried run this code but I have an error:

a4 local variable referenced before assignment

a1 = '/fr/store/a'
try:
   a2 = '/fr/store/b/collection/3432'
   a2_store = "store"
   a3 = a2.split ("store/")
   a4 = a3[0]
   if a2_store in a2:
      print ('a2')
except:
   if a4 not in a1:
      print ('a1')

I didn't get an error running your code. I got `a2` printed. Please provide a [mre]. You can [edit] the question. BTW welcome to SO! Check out the [tour] and [ask] if you want more advice. — wjandrea, May 19 '20 at 17:27
I'm not sure if it's part of the problem, but a [bare `except` is bad practice](https://stackoverflow.com/a/54948581/4518341). Try switching it to `except IndexError` and see if the issue continues. — wjandrea, May 19 '20 at 17:29

score 1 · Answer 1 · answered May 19 '20 at 17:24

1

If an exception is raised before a4 = a3[0] is executed (for example, if a3[0] raises an IndexError), then a4 is, indeed, not defined.

answered May 19 '20 at 17:24

chepner

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The example is self-contained actually, and there's no error when you run it – wjandrea May 19 '20 at 17:26
Oh but an exception could come from elsewhere, like a KeyboardInterrupt, since they're using a bare `except`. hmm... – wjandrea May 19 '20 at 17:28

try and if - local variable referenced before assignment

1 Answers1