Do you need to use name=main statement for running any script in python?

Question

I just wanted to understand why you have to use if __name__ == '__main__': if we can run any python script even without using that statement. For example, I can run this script without using it:

def hello():
      print("hello")
      return 1234

# And here is the function being used
print(hello())

Well, it's not why you *have to* use that statement, it's why you might *want to*. — Greg Hewgill, Aug 05 '12 at 01:55
You usually never want side effects from importing a module, like having it run a bunch of operations on you. — jdi, Aug 05 '12 at 01:57

score 5 · Answer 1 · answered Aug 05 '12 at 01:54

5

It's done so that code is only executed when run as a script and not when you import the module.

answered Aug 05 '12 at 01:54

jamylak

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score 0 · Answer 2 · answered Aug 05 '12 at 02:40

0

Code in the global namespace runs slightly slower. It's easy to make a main() function, so why not do it? It is optional though if you don't mind the module "running" when you import it

answered Aug 05 '12 at 02:40

John La Rooy

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Do you need to use __name__=__main__ statement for running any script in python?

2 Answers2

Do you need to use name=main statement for running any script in python?