FAQ Try-Except

Goal

Learn to use try-expect blocks to enhance the readability of the program, to avoid program crash, and to understand the error messages.

Introduction

In Python, try-except blocks are an exception handling mechanism. Exceptions allow a program to gracefully manage errors that occur during runtime without crashing. Try-except blocks allow users to insert codes to handle errors, to record errors, to display error messages, or to execute other programs.

Example

## try-except 
try:
    # Program segment potentially generates an erorr 
    risky_code()
except Exception as e:
    # Display an error message
    print('Error Msg:{}'.format(e))

Example 1: Design a busy_function

try:
    import time 
    def busy_function(duration):
        print('Busy function starting for {} seconds...'.format(duration))
        start_time = time.time()
        while time.time() - start_time < duration:
            #Continue or keep busy 
            _ = 0
            for i in range(10000):
                _ += i        
        print("Busy function completed.")
    # Allows busy_function to execute for 20 more seconds
    busy_function(20)   
except Exception as e:
    # Displly an error massage
    print('Error Msg:{}'.format(e))

Conclusion

Users can include import, def, or the main program into a try-except block to ensure that the program will not crash when an error occurs. In addition, error messages can be shown to flag the potential causes. Mastering try-except blocks can enhance the efficiency of the program debugging.