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Date: Wed, 31 Oct 2012 00:18:57 +1100
Subject: Re: exec with partial globals
From: Chris Angelico <rosuav@gmail.com>
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On Tue, Oct 30, 2012 at 11:57 PM, Helmut Jarausch
<jarausch@igpm.rwth-aachen.de> wrote:
> Given spreadsheet  S (Source) and D (Destination) as objects (wrapping a
> dictionary) a possible (legal) input would be
>
> D.price= D.price-S.discount
>
> No other fields of 'D' should be modifiable.

That's a bit harder. What you're describing, using exec with specific
globals, would not be able to do this. You'd need to build a proxy
object that decides whether or not to pass on the change.

ChrisA