Syntax error break outside loop python

The break statement terminates the current loop and resumes execution at the next statement. You can only use a break statement inside a loop or an if statement. If you use a break statement outside of a loop, then you will raise the error “SyntaxError: ‘break’ outside loop”.

SyntaxError: ‘break’ outside loop

What is SyntaxError?

Syntax refers to the arrangement of letters and symbols in code. A Syntax error means you have misplaced a symbol or a letter somewhere in the code. Let’s look at an example of a syntax error:

number = 23

print()number

    print()number
           ^
SyntaxError: invalid syntax

The ^ indicates the precise source of the error. In this case, we have put the number variable outside of the parentheses for the print function, and the number needs to be inside the parentheses to print correctly.

print(number)

23

What is a Break Statement?

Loops in Python allow us to repeat blocks of code. In cases, Sometimes conditions arise where you want to exit the loop, skip an iteration, or ignore a condition. We can use loop control statements to change execution from the expected code sequence, and a break statement is a type of loop control statement.

A break statement in Python brings the control outside the loop when an external condition is triggered. We can put an if statement that determines if a character is an ‘s‘ or an ‘i‘. If the character matches either of the conditions the break statement will run. We can use either a for loop or a while loop. Let’s look at an example where we define a string then run a for loop over the string.

string = "the research scientist"

for letter in string:

    print(letter)

    if letter == 's' or letter == 'i':

        break

print("Out of the for loop")

t
h
e
 
r
e
s
Out of the for loop

The for loop runs until the character is an ‘s‘ then the break statement halts the loop. Let’s look at the same string example with a while loop.

i = 0

while True:

    print(string[i])

    if string[i] =='s' or string[i] == 'i':

        break

    i += 1

print(Out of the while loop")

t
h
e
 
r
e
s
Out of the while loop 

We get the same result using the while loop.

Example: If Statement

Let’s look at an example where we write a program that checks if a number is less than thirty. We can use an input() statement to get input from the user.

number = int(input("Enter an appropriate number "))

Next, we can use an if statement to check whether the number is less than thirty.

if number ≺ 30:

    print('The number is less than 30')

else:

    break

Suppose the number is less than thirty, the program prints a message to the console informing us. Otherwise, a program will run a break statement. Let’s run the program and see what happens:

Enter an appropriate number: 50

    break
    ^
SyntaxError: 'break' outside loop

The program returns the SyntaxError: ‘break’ outside loop because the break statement is not for breaking anywhere in a program. You can only use a break statement within a loop.

Solution

To solve this problem, we need to replace the break statement with an exception that stops the program if the number exceeds thirty and provides an exception message. Let’s look at the revised code.

number = int(input("Enter an appropriate"))

if number ≺ 30:

    print('The number is less than 30')

else:

    raise Exception("The number is not less than 30")

We replaced the break statement with a raise Exception.

<meta charset="utf-8">Enter an appropriate number: 50

Exception                                 Traceback (most recent call last)
      2     print('The number is less than 30')
      3 else:
----≻ 4     raise Exception('The number is greater than 30')
      5 

Exception: The number is greater than 30

If the number is greater than thirty the program will raise an exception, which will halt the program.

Summary

Congratulations on reading to the end of this tutorial! The error “SyntaxError: ‘break’ outside loop” occurs when you put a break statement outside of a loop. To solve this error, you can use alternatives to break statements. For example, you can raise an exception when a certain condition is met. You can also use a print() statement if a certain condition is met.

Go to the online courses page on Python to learn more about Python for data science and machine learning.

Have fun and happy researching!

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A break statement instructs Python to exit a loop. If you use a break statement outside of a loop, for instance, in an if statement without a parent loop, you’ll encounter the “SyntaxError: ‘break’ outside loop” error in your code.

In this guide, we’re going to discuss what this error means and why you may see it. We’ll explore an example of this error so you can learn how to fix the error.

SyntaxError: ‘break’ outside loop

The Python break statement acts as a “break” in a for loop or a while loop. It stops a loop from executing for any further iterations.

Break statements are usually enclosed within an if statement that exists in a loop. In such a case, a programmer can tell a loop to stop if a particular condition is met.

A break statement can only be used inside a loop. This is because the purpose of a break statement is to stop a loop. You can use a break statement inside an if statement, but only if that if statement is inside a loop.

An Example Scenario

Let’s write a program that validates a username for a game. A username must be under twelve characters long to be valid. A username must not contain any spaces.

To validate our username, we’re going to use two if statements. To start, let’s ask a user to choose a username for our game using an input() statement:

username = input("Enter your new username: ")

Next, let’s use an if statement to check whether our username is less than 12 characters long:

if len(username) < 12:
	print("This username is the right number of characters.")
else:
	break

If the username a user inserts into the program is fewer than 12 characters, our program prints a message to the console informing us that the username is of the correct length. Otherwise, a break statement will run.

Next, let’s validate whether that the username does not contain a space:

if " " not in username:
	print("This username is valid.")
else:
	break

We use an if...in statement to check for a character in the “username” string. We check for a blank space. This blank space is enclosed within the two quotation marks in our if statement.

If a username contains a space, a break statement executes. The break statement is part of the else statement in our code.

Let’s run our code and see what happens:

  File "main.py", line 6
	break
	^
SyntaxError: 'break' outside loop

Our code returns an error.

The Solution

We’ve used a break statement to halt our program if one of our criteria is not met when validating a user’s username.

This causes an error because the break statement is not designed to start a break anywhere in a program. The break statement only stops a loop from executing further.

To fix our code, we need to remove the break statements. We can replace them with an exception that stops our program and provides an error message:

if len(username) < 12:
	print("This username is the right number of characters.")
else:
	raise Exception("Your username must be under twelve characters.")

if " " not in username:
	print("This username is valid.")
else:
	raise Exception("Your username cannot contain space.s")

If the length of a username is equal to or greater than 12, or if a username contains a space, our program will raise an exception. This exception will stop our program from continuing.

Let’s run our code:

Enter your new username: bill3
This username is the right number of characters
This username is valid

Our code runs successfully if our username is valid. Let’s see what happens if we enter an invalid username:

Enter your new username: bill 3
This username is the right number of characters
Traceback (most recent call last):
  File "main.py", line 11, in <module>
	raise Exception("Your username cannot contain spaces")
Exception: Your username cannot contain spaces

Our code returns an exception. Alternatively, we could have used print statements to inform the user that their username was incorrect. This would only be suitable if we wanted our program to continue, or if we had a loop that ran until a username validated successfully.

Conclusion

The “SyntaxError: ‘break’ outside loop” error is raised when you use a break statement outside of a loop.

To solve this error, replace any break statements with a suitable alternative. To present a user with a message, you can use a print() statement. To halt execution of your program when a condition is met, you can raise an exception.