CMU 15-112: Fundamentals of Programming and Computer Science
Class Notes: Exceptions

1. Basic Exception Handling (try/except)   video
   

   print("This is a demonstration of the basics of try/except.")
   try:
       print("Here we are just before the error!")
       print("1/0 equals:", (1/0))
       print("This line will never run!")
   except:
       print("*** We just caught an error. ***")
   print("And that concludes our demonstration.")

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2. Raising an Exception

   def lastChar(s):
       if (len(s) == 0):
           # This is (a simple form of) how you raise your own custom exception:
           raise Exception('String must be non-empty!')
       else: return s[-1]
   
   print(lastChar('abc'))
   print(lastChar(''))
   print("This line will never run!")

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