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Python Python Basics Functions and Looping Exception Flow

Posted by Simone O
Simone O
405 Points

Why does the result not include B or E?

spoiler quiz question for exception handling. I ran the code in the workspace after i got it wrong but can someone walk me through this. I am not understanding.

print("A") try: result = "test" + 5 print("B") except ValueError: print("C") except TypeError: print("D") else: print("E") print("F")

2 Answers

Pedro Cabral
Pedro Cabral
33,586 Points
Pedro Cabral
Pedro Cabral
33,586 Points 
print("A")
try:
  result = "test" + 5 # let's call foo
  print("B") # let's call this bar
except ValueError:
  print("C") # if foo OR bar throw a value error then this line will run 
except TypeError:
  print("D") # if foo OR bar throw a type error then this line will run
else:
  print("E") # if foo AND bar run successfully, this line will run - in other words, only if the try doesn't throw an exception.
  print("F") # if foo AND bar run successfully, this line will run - in other words, only if the try doesn't throw an exception.

If foo throws an error, then bar will never be executed because the code flow will either: jump to the except block or throw an exception if the except block is not there to catch it.

To answer your question, B will never run because the program "blew up" while executing the line above (foo). You can't add a number to a string, and that error is a TypeError because it was expecting the int 5 to be of type str "5". The E and F won't run, because the code inside the try did not execute with success.

Try to edit foo to

result = "test" + 5

and see the results.

Simone O
Simone O
405 Points
Simone O
Simone O
405 Points

thank you! The lightbulb just clicked. :)