Hello everyone.
i have a question about defining a main function. I’ve had used it alot but now that i think of it’s not quite clear to me that why i should define such thing.
specially the following syntax
if __name__ == "__main__":
main()
Many Python files contain only function (and class) definitions. If you “run” (or import) these files, they “do nothing”. They define functions/classes but do not run any of the code. This is perfect for libraries/modules which define objects that other code could use.
Some Python files contain “top level” code that runs when the file is “run” (or imported). These files “do stuff” when you run them. This is entirely fine for files that are supposed to do something; however, these files then are not very useful if you want to load their function/class definitions, ie if you want to test the code and/or use the file as a library/module.
The if __name__ == "__main__" clause allows a file to be used either way. If the file is run directly, Python sets __name__ to __main__ and the “main” code can be executed. If the file is being imported by another file, ie it is being used as a library, the __name__ is set to the module name and the main code is not run.
4 Likes
thank you so much.
one more thing is that i’m not really familiar with modules and libraries.
where do you suggest to read about them?
does this topic have any specific names?
2 Likes
I recommend you to google Modules or Library Documentation. There is tons of information in them, which can be very helpful.
No need to Google them ;) I provided the links in my prior message.