[Python-ideas] PEP for executing a module in a package containing relative imports

Christian Heimes lists at cheimes.de
Fri Apr 20 15:43:21 CEST 2007

Brett Cannon schrieb:
> When a module is being executed as a script, ``__main__`` will be set
> to a true value.  For all other modules, ``__main__`` will be set to a
> false value.  This changes the current idiom of::
>   if __name__ == '__main__':
>       ...
> to::
>   if __main__:
>       ...
> The current idiom is not as obvious and could cause confusion for new
> programmers.  The proposed idiom, though, does not require explaining
> why ``__name__`` is set as it is.
> With the proposed solution the convenience of finding out what module
> is being executed by examining ``sys.modules['__main__']`` is lost.
> To make up for this, the ``sys`` module will gain the ``main``
> attribute.  It will contain a string of the name of the module that is
> considered the executing module.

What about

    import sys
    if __name__ == sys.main:

You won't have to introduce a new global module var __name__ and it's
easy to understand for newbies and experienced developers. The code is
only executed when the name of the current module is equal to the
executed main module (sys.main).
IMO it's much less PIT...B then introducing __main__.


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