What is the best way to exit a function (which has no return value) in python before the function terminates (e.g. check failed)?

Question

Suppose an iteration is called a function with no return value. I think my program should behave, explained in this pseudo code:

for element in some_list: foo(element) def foo(element): do something if check is true: do more (because check was succesful) else: return None do much much more... 

If I implement this in python, it bothers me that the function returns None . Is there a better way to "exit a function that does not have a return value if the test fails in the body of the function"?

Answer 1

You can just use

 return 

which does the same thing as

 return None 

Your function will also return None if execution reaches the end of the function body without pressing the return . The return does not match the return of None in Python.

Answer 2

I would suggest:

 def foo(element): do something if not check: return do more (because check was succesful) do much much more... 

Answer 3

you can use the return without any parameters to exit the function

 def foo(element): do something if check is true: do more (because check was succesful) else: return do much much more... 

or throw an exception if you want to get information about the problem

 def foo(element): do something if check is true: do more (because check was succesful) else: raise Exception("cause of the problem") do much much more... 

Answer 4

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