6.6 Loop control statements

Loop control statements in Python - break, continue, and pass allow us to control the flow of loops (for-in and while loops).

6.6a break statement

The break statement terminates the loop entirely. When break is encountered inside a loop, the loop stops immediately, and the program continues with the next statement following the loop.

Example 6.6.1 - In this example, the loop will print numbers from 0 to 4. When i is 5, the break statement is executed, and the loop terminates.

for i in range(10):
    if i == 5:
        break
    print(i)

Example 6.6.1 - Output

0
1
2
3
4

6.6b continue statement

The continue statement skips the rest of the code inside the loop for the current iteration and moves to the next iteration of the loop.

Example 6.6.2 - In this example, the loop will print only the odd numbers from 0 to 9. When i is an even number, the continue statement is executed, and the rest of the code inside the loop is skipped for that iteration.

for i in range(10):
    if i % 2 == 0:
        continue
    print(i)

Example 6.6.2 - Output

1
3
5
7
9

6.6c pass statement

The pass statement is a null operation; nothing happens when it is executed. It’s used as a placeholder for future code. This can be useful in places where your code requires a statement syntactically, but you haven’t decided what to do there yet.

Example 6.6.3 - In this example, the pass statement is used as a placeholder within the if block. It doesn’t affect the loop’s execution.

for i in range(10):
    if i % 2 == 0:
        pass  # Placeholder for future code
    else:
        print(i)

Example 6.6.3 - Output

1
3
5
7
9

6.6d Summary of loop control statements

• break - Exits the loop immediately.
• continue - Skips the rest of the code inside the loop for the current iteration and proceeds to the next iteration.
• pass - Does nothing; it's a placeholder that allows you to write syntactically correct empty code.