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Date: Sun, 18 Aug 2013 02:07:16 +0100
Subject: Re: Python getters and setters
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:52648

On Sun, Aug 18, 2013 at 12:40 AM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> The Law of Demeter is really about being careful about what interface
> your classes provide. Customers should provide a get_payment method; dogs
> should provide a walk method. You shouldn't have to send individual step
> messages to the dog's legs.

And it has its limits, too. If you're walking a dog on a leash, you
don't send a message to the leash to send a message to the dog to
walk. You talk directly to the dog. Like most programming principles,
it's something to read, to grok, and then to think about. I have yet
to find any rule which, if slavishly followed, will not lead to bad
code _somewhere_.

ChrisA