Python exit from if loop

Exit if Statement in Python

The if statement is one of the most useful and fundamental conditional statements in many programming languages. We use the if statement to check whether a condition is True or False and execute some code based on the result. We generally provide an alternative code, which is to be executed when the condition of the if statement fails, using the else statement.

Exit if Statement in Python

This tutorial will demonstrate how to exit if statement in Python.

Using the break statement

The break statement is used to break out of a loop in Python. We cannot directly use this with the if statement. However, we can work around it using a loop.

We can use the while loop and create an infinite loop by providing a True condition. We put the if statement within this loop and use the break statement whenever we want to exit if statement in Python. It will directly break out of the loop and resume program execution.

We implement this in the code below.

In the above example, we can observe that the if statement is exited after encountering the break statement.

Using the return statement

We use the return statement whenever we define a function to return some value. The function execution is exited automatically whenever the return statement is encountered in the function definition. If the return statement is missing then the function returns None value by default.

We can put the if statement within the function and use the return statement to exit the function definition which automatically exits the if statement.

Further reading:

Exit program in Python

Break out of function in Python

Using the try and except statements

Python is efficient in exception handling. Exceptions are the errors that are encountered within the code that disrupt program execution. There are different types of exceptions in Python.

The try and except statements are used to work with exceptions in Python. We put code that may raise an exception within the try block. We put an alternative code within the except block. If the code in the try block raises an exception, then the code of except block is executed.

To raise manual exceptions we use the raise statement. We can use a combination of these statements to exit if statement in Python.

We can raise an exception in the if block. Whenever this exception is raised, the program execution goes to the except block. We can put the pass keyword in the except code block which executes nothing when encountered.

The above-mentioned logic is implemented below.

Conclusion

To conclude, we discussed several methods to exit if statement in Python. There are no direct methods available for the same, so we use different methods in which we shift control to some other part of the program.

In the first method, we use the break statement to exit if statement in Python. The if statement is put within the while loop and program execution comes out of the loop when the break statement is encountered within the if statement.

In the second method, we use the return statement to exit if statement in Python. We put the if statement within a function and the return statement is used to exit the function when it is encountered.

We use the try and except statements in the final method and use exception-handling to exit if statement in Python. We manually raise an exception within the if statement to exit the statement and resume program execution.

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Break for loop in an if statement [duplicate]

Currently having trouble with breaking this for loop. I want to break it if the variable is not found in this list so it can move two another for loop. It expects an indented block for the top of the for loop, but if I change the position of the break or of the start of the for loop, it doesn’t work. Help!

break only breaks out of the inner loop, not the outer loop. Are you sure you need the inner loops? Maybe it should just be if x in lowercaselist

At first glance, your indentation seems incorrect. Does the first else go against the first if x in z? Then it should be indented to the same level as the first if. Does the third for statement go under that else? Then everything should be indented one level deeper than the else.

What’s the value of lowercaselist and uppercaselist ? Are they lists of lists? That’s whay it looks like when you’re looping over them and then using x in z .

Then why are you using x in z instead of just x = z ? Or why don’t you just write if x in lowercaselist: ?

1 Answer 1

You’ll need to break out of each loop separately, as people have mentioned in the comments for your question, break only stops the loop which it’s in

for x in userpassword[k]: for z in lowercaselist: if x in z: newpasswordlist.append(z) k +=1 break if x in z: # added an extra condition to exit the main loop break 

You’ll need to do this for both loops. If you want to break out of the while loop as well, then you can add if x in z: break in that loop as well.

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Exit the if Statement in Python

1. Exit an if Statement With break in Python
2. Exit an if Statement With the Function Method in Python

This tutorial will discuss the methods you can use to exit an if statement in Python.

Exit an if Statement With break in Python

The break is a jump statement that can break out of a loop if a specific condition is satisfied. We can use the break statement inside an if statement in a loop.

The main purpose of the break statement is to move the control flow of our program outside the current loop. The program below demonstrates how you can use the break statement inside an if statement.

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

We developed a program using the break statement that exits the loop if the value of the variable i becomes equal to 5 . The only thing missing with this approach is that we can only use it inside an if statement enclosed inside a loop. We cannot use this inside a nested if statement, as shown below.

i =0 if i%2 == 0:  if i == 0:  break  if i > 0:  print("even") print("Broken") 

File "", line 4  break  ^ SyntaxError: 'break' outside loop 

If we want to exit out of a pure if statement that is not enclosed inside a loop, we have to utilize the next approach.

Exit an if Statement With the Function Method in Python

We can use an alternative method to exit out of an if or a nested if statement. We enclose our nested if statement inside a function and use the return statement wherever we want to exit.

The following code modifies the previous example according to the function method.

def something(i):  if i%2 == 0:  if i == 0:  return  if i > 0:  print("even")  if __name__ == "__main__":  something(0)  print("Broken out") 

We developed a program that uses the function method to exit out of multiple if statements with the return statement. This method is clean and far superior to any other methods that can be used for this purpose.

A lot of forums mention another method for this purpose involving a goto statement. By default, we know that Python has no support for a goto statement.

But, in 2004, a goto module was released as part of an elaborate April fools day joke that users began to use seriously. We didn’t mention it because it is not a graceful method and its official page notes that it should never be used inside any production code.

Maisam is a highly skilled and motivated Data Scientist. He has over 4 years of experience with Python programming language. He loves solving complex problems and sharing his results on the internet.

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