Implementing a Python decorator for exception handling with a default response

Last update on March 29 2025 13:16:33 (UTC/GMT +8 hours)

9. Implement a decorator to handle exceptions with a default value

Write a Python program that implements a decorator to handle exceptions raised by a function and provide a default response.

Sample Solution:

Python Code:

def handle_exceptions(default_response):
    def decorator(func):
        def wrapper(*args, **kwargs):
            try:
                # Call the original function
                return func(*args, **kwargs)
            except Exception as e:
                # Handle the exception and provide the default response
                print(f"Exception occurred: {e}")
                return default_response
        return wrapper
    return decorator

# Example usage
@handle_exceptions(default_response="An error occurred!")
def divide_numbers(x, y):
    return x / y

# Call the decorated function
result = divide_numbers(7, 0)  # This will raise a ZeroDivisionError
print("Result:", result)

Sample Output:

Exception occurred: division by zero
Result: An error occurred

Explanation:

In the above exercise -

The 'handle_exceptions' decorator takes a default response as an argument. It then defines a decorator function that wraps around the original function. Within the wrapper function, the original function is called within a try-except block. In the case of an exception during the execution of the original function, the default response is returned instead.

In the example usage, the 'divide_numbers' function is decorated with @handle_exceptions(default_response="An error occurred"). When 'divide_numbers' is called with '7' and '0', a 'ZeroDivisionError' will be raised. However, the decorator catches the exception, prints an error message, and returns the default response "An error occurred".

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python decorator that catches any exception raised by a function and returns a default value instead.
• Write a Python decorator that handles specific exceptions (like KeyError, IndexError) and logs a warning before returning a fallback result.
• Write a Python decorator that retries a function upon catching an exception, and if it still fails, returns a default value.
• Write a Python decorator that wraps a function in a try-except block to handle errors and provides a user-friendly error message if an exception occurs.

Python Code Editor :

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