Re: [PLUG] Off Topic: Python3 Global Variable in Separate Function File Question

[Paul Jungwirth <pj@illuminatedcomputing.com>]

On 09/03/2018 08:05 AM, Casey Bralla wrote:
> Sorry for the off-topic, but I'm running Python3 on Linux :)
>
>
> I'm confused by global variables in functions that are kept in separate
> files.
>
> I understand that in Python3 variables are "inherited" into functions,
> and that to make them global, they have to be declared as global within
> the function.  However, if I put all my functions in a separate file and
> import them, the variables that should be global are NOT global.

This StackOverflow answer should help you out:

https://stackoverflow.com/questions/15959534/python-visibility-of-global-variables-in-imported-modules/15959638

The key line is:

> Globals in Python are global to a module, not across all modules.

You can make your script work with two changes:

1. In the imported module, make sure your variable is defined at the 
top-level as soon as the file is imported, whether you ever call the 
function or not:

    Parameter3 = 0
    def testglobal(Parameter1, Parameter2):
        ...

2. In the test script, do `import globalmodules`, not (or in addition 
to) `from globalmodules import *`. Then refer to `globalmodules.Parameter3`.

--
Paul              ~{:-)
pj@illuminatedcomputing.com
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