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Date: Mon, 20 Jul 2015 08:40:36 +1000
Subject: Re: Is this a good way to work with init and exception
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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On Mon, Jul 20, 2015 at 8:19 AM, Cecil Westerhof <Cecil@decebal.nl> wrote:
>> If two modules import the same module, they get two references to
>> that same module, not two separate module instances. Since your
>> parameters appear only to affect the initialization itself, this is
>> not likely to be a problem (it's not like you'll need to
>> authenticate with two different sets of credentials, for instance),
>> but it will mean that the second one will import an
>> already-initialized module. That's why I suggested the try_init
>> function which would quietly return an immediate success if the
>> module had already been initialized. But if this isn't going to be
>> an issue, then your code's fine.
>
> Good to know. I would expect two different instances.
>
> I agree that in my case it would not be a problem, but I put the code
> on GitHub:
>     https://github.com/CecilWesterhof/PythonLibrary/blob/master/twitterDecebal.py
> I should do my best to circumvent nasty surprises for users of the
> code. Someone else could use several Twitter accounts at the same
> time. Is there a way to do this?

Does the instantiation of Core() involve authentication? Is it
possible to call Core() more than once and use different accounts?
Your send_message() takes an account identifier, so it might be you
don't need separate accounts. But if, just very occasionally, you do
need multiple, here's a possible design style: Have init() return the
Core as well as stashing it in _core, and then have send_message()
take an optional keyword argument (in 3.x, keyword-only) to choose a
different core. That way, it'll by default use the most recently
initialized core, but you can create multiple and manage them yourself
if you so choose. (Obviously you'd use reinit_allowed=True for all the
initializations.)

ChrisA