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Date: Mon, 8 Jul 2013 10:46:59 +1000
Subject: Re: Default scope of variables
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:50111

On Mon, Jul 8, 2013 at 2:03 AM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> If you need more than two levels, you probably ought to re-design your
> code to be less confusing, otherwise you may be able to use ChainMap to
> emulate any number of nested scopes.

The subtransactions are primarily to represent the database equivalent
of a try/except block, so they need to be able to be nested
arbitrarily.

ChrisA