[Python-ideas] Replacing the if __name__ == "__main__" idiom (was Re: making a module callable)

[Ron Adam]

On 11/25/2013 09:15 AM, Chris Angelico wrote:
> On Tue, Nov 26, 2013 at 1:55 AM, Ron Adam <ron3200 at gmail.com> wrote:
>> But when there is only *one* of something, and you aren't manipulating the
>> parts, then "is" should be ok.  __name__ would be bound directly to
>> __main__'s string object, so "is" or "==" should always work for that case.
>
> Really? Is this something that's guaranteed? I know the CPython
> compiler will optimize a lot of constants, but can you really be sure
> that this is safe?


It seems to me, that you can't do this ...

        if __main__ is "__main__":

That depends on the compiler to optimise that case so they are the same object.


But in this case...

        __main__ = "__main__"
        __name__ = __main__
        assert __main__ is __name__

That should always work.  I would think it was a bug if it didn't.

Cheers,
    Ron