Data Type Conversions

Error Handling

Python uses try-except blocks to handle errors gracefully. This prevents your program from crashing when unexpected situations occur.

try:
    # Code that might raise an exception
    result = 10 / 0  # This will cause a ZeroDivisionError
except ZeroDivisionError:
    # Handle the specific exception
    print("Error: Division by zero")
except Exception as e: # Catches all other exceptions
    print(f"An unexpected error occurred: {e}")
else: #Executes if no exception occurs
    print(f"Result: {result}")
finally: # Always executes, regardless of exceptions
    print("This always runs")

Exception Handling Specifics (This will be a separate note detailing different exception types, best practices, and custom exceptions)

Common Exceptions:

ZeroDivisionError: Division by zero.
TypeError: Incompatible data types in an operation.
ValueError: Inappropriate value passed to a function.
FileNotFoundError: Attempting to open a non-existent file.
IndexError: Accessing a list or tuple index out of bounds.
KeyError: Accessing a dictionary key that doesn’t exist.

Example of catching multiple exceptions:

try:
  file = open("my_file.txt", "r")
  #Process file
  content = file.read()
  data = int(content)

except (FileNotFoundError, ValueError) as e:
    print(f"Error processing file: {e}")
finally:
  file.close() # important to close the file, regardless of success or failure

Custom Exceptions (This note will explain how to define your own exception classes to manage specific error conditions in your code)

Related Notes:

File Handling (This will discuss file I/O operations and related error handling)

Error Handling

Carson West

Data Type Conversions

Error Handling