Passing information between modules

[Thomas Passin]

On 11/19/2022 4:28 PM, Thomas Passin wrote:
> On 11/19/2022 3:46 PM, Michael F. Stemper wrote:
>> On 18/11/2022 04.53, Stefan Ram wrote:
>>>    Can I use "sys.argv" to pass information between modules
>>>    as follows?
>>>
>>>    in module A:
>>>
>>> import sys
>>> sys.argv.append( "Hi there!" )
>>>
>>>    in module B:
>>>
>>> import sys
>>> message = sys.argv[ -1 ]
>>
>> I just tried and it appears that one can append to sys.argv. However,
>> it seems like an incredibly bad idea.
> 
> For that matter, you can just directly add attributes to the sys module, 
> no need to use sys.argv:
> 
>  >>> import sys
>  >>> sys._extra = 'spam'   # Not an exception
>  >>> print(sys._extra)
> spam
> 
> Probably not the best idea, though.  Better to use some module that you 
> control directly.

This could be one of those things of which Raymond Chen (The Old New 
Thing) asks "what if everyone did this?".  Imagine if every 
(non-standard-library) module misused sys or sys.argv like this.  The 
result could be chaotic.

Best to put all your own stuff into modules that you yourself control.