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Date: Wed, 10 Jun 2015 09:06:27 +1000
Subject: Re: enhancement request: make py3 read/write py2 pickle format
From: Chris Angelico <rosuav@gmail.com>
Cc: "comp.lang.python" <python-list@python.org>
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On Wed, Jun 10, 2015 at 6:07 AM, Devin Jeanpierre
<jeanpierreda@gmail.com> wrote:
> There's a lot of subtle issues with pickle compatibility. e.g.
> old-style vs new-style classes. It's kinda hard and it's better to
> give up. I definitely agree it's better to use something else instead.
> For example, we switched to using protocol buffers, which have much
> better compatibility properties and are a bit more testable to boot
> (since text format protobufs are always output in a canonical (sorted)
> form.)

Or use JSON, if your data fits within that structure. It's easy to
read and write, it's human-readable, and it's safe (no chance of
arbitrary code execution). Forcing yourself to use a format that can
basically be processed by ast.literal_eval() is a good discipline -
means you don't accidentally save/load too much.

ChrisA