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Date: Fri, 31 Aug 2012 12:06:04 +0100
From: Chris Withers <chris@python.org>
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To: Ben Finney <ben+python@benfinney.id.au>
Subject: Re: Context manager to save/restore a name binding
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Xref: csiph.com comp.lang.python:28168

Hi Ben,

On 31/08/2012 03:36, Ben Finney wrote:
> That way, I can set ‘sys.dont_write_bytecode’ to the value I need in
> this part of the code, knowing that however the code continues the
> previous value of that setting will be restored to whatever it was
> before I touched it.
>
> Have I re-invented a context manager which already exists? Is there a
> better way to do what ‘preserve_value’ is doing?

Depends on the context (ho ho..), but if it's testing, then have a look at:

http://packages.python.org/testfixtures/mocking.html#the-context-manager

There's plenty of other goodies you may like in there too...

cheers,

Chris

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