Python Debugger may be a new word for the beginner developers . In this post , we will try to explain the meaning of Debugging and Debugging with Python .
What is Debugging?
Debugging means the complete control over the program execution. Developers use debugging to overcome program from any bad issues. So debugging is a healthier process for the program and keeps the diseases bugs far away. Python also allows developers to debug the programs using pdb module that comes with standard Python by default. We just need to import pdb module in the Python script. Using pdb module, we can set breakpoints in the program to check the current status. We can Change the flow of execution by using jump, continue statements . Let’s understand debugging with a Python program.
Example:
Python3
# Program to print Multiplication # table of a Number n=5for x in range(1,11) : print( n , '*' , x , '=' , n*x ) |
Output:
5 * 1 = 5 5 * 2 = 10 5 * 3 = 15 5 * 4 = 20 5 * 5 = 25 5 * 6 = 30 5 * 7 = 35 5 * 8 = 40 5 * 9 = 45 5 * 10 = 50
This program simply print multiplication table but now we need to debug the loop steps using set_trace() function call to pdb module .
Example:
Python3
# Python Program to print Multiplication Table # We want to debug the for loop so we use # set_trace() call to pdb module import pdb # It means , the Start of Debugging Mode pdb.set_trace() n=5for x in range(1,11) : print( n , '*' , x , '=' , n*x ) |
Output:
Basic Commands to use Python Debugger
list command to see entire program .
list command
list 3 , 6 to see the program lines from 3 to 5 only .
list lines command in pdb debugger
break command to stop the program execution at particular line .
break command in pdb debugger
continue command to see the next step in the loop .
continue command in pdb debugger
jump command allows us to go on any particular line in the program .
jump command in pdb debugger
pp command to see variable value at the current position in the program .
pp command in pdb debugger
disable command to disable the current line output and we can use continue command to skip this line in program. We use quit or exit command to come outside the debugging mode .
Conclusion
Debugging helps developers to analyze programs line by line. Developers see the every interpreted line by using debugging mode in programs. Python comes with by default debugger that is easy to import and use. So it is good to start with debugger when confused about execution of large loops, current variable values and all .
