Functions, Finally, and Custom Exceptions

These three concepts are essential for writing robust and maintainable Python code. Here's a breakdown of each:

Functions:

  • Reusable blocks of code that perform a specific task.
  • Defined using the def keyword followed by the function name and parentheses.
  • Can take arguments (inputs) and return values (outputs).
  • Promote code modularity and reusability.

Example:

Python
def greet(name):
  """Prints a greeting message."""
  print(f"Hello, {name}!")

greet("Alice")  # Output: Hello, Alice!

Finally:

  • A block of code that always executes, regardless of whether an exception occurs in the try block.
  • Used for essential tasks like closing files or releasing resources.
  • Ensures these tasks are completed even if an error happens.

Example:

Python
try:
  # Code that might raise an exception
  with open("data.txt", "r") as file:
    data = file.read()
except FileNotFoundError:
  print("Error: File not found")
finally:
  # Always executed, even if there's no exception
  print("File closed")

Custom Exceptions:

  • User-defined exceptions to handle specific errors in your program.
  • Inherit from the built-in Exception class.
  • Provide informative error messages and allow for specific handling.

Example:

Python
class InvalidAgeError(Exception):
  """Raised when an invalid age is provided."""
  pass

def check_age(age):
  if age < 0:
    raise InvalidAgeError("Age cannot be negative")
  # Rest of the code

try:
  check_age(-5)
except InvalidAgeError as e:
  print(f"Error: {e}")

Key Points:

  • Functions help organize code and improve readability.
  • finally ensures critical tasks are executed.
  • Custom exceptions provide better error handling and clarity.

By effectively using these concepts, you can write more robust and maintainable Python applications.

Pesquisar
Categorias
Leia Mais
Technology
Importance of Ethical Behavior to a User
Ethical behavior in the use of technology is crucial for users, as it directly impacts their...
Por ALAGAI AUGUSTEN 2024-07-13 07:22:05 0 10K
Educação
ECONOMICS MOCK
https://acrobat.adobe.com/id/urn:aaid:sc:EU:ec617028-2a6c-4082-b406-54df86b57b55
Por Landus Mumbere Expedito 2024-07-24 19:44:22 0 8K
Technology
Everything You Need to Know Before Starting with TebTalks
Por Mpatswe Francis 2024-09-03 22:02:03 0 12K
Educação
S.4 PHYSICAL EDUCATION MOCK EXAM
https://acrobat.adobe.com/id/urn:aaid:sc:EU:ec617028-2a6c-4082-b406-54df86b57b55
Por Landus Mumbere Expedito 2024-07-24 19:32:08 0 11K
Outro
Turkish Airlines Flight Makes Emergency Landing at JFK After Pilot Dies
New York, October 9, 2024 – A Turkish Airlines flight from Seattle to Istanbul made an...
Por Updates & History 2024-10-09 17:55:15 0 13K
Tebtalks https://tebtalks.com