This is an old revision of the document!
if __name__ main
Many python source files include a section like this:
if __name__ == '__main__': main()
It may include other statements as well.
This special if statement is checked by the python interpreter itself when it reads the source file.
- If the source is being run as the main program, it sets that source file as the special “name” variable to “main”.
- If the source file is being imported from another module, the “name” variable will be set to the module's name instead.
The entire reason behind this is:
- Sometimes modules are written to be executed directly.
- They could also be imported for use in another module.
- The main check allows for only the “main” code to execute if run directly and not if someone imports the module to call functions.