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To: python-list@python.org
From: "Frank Millman" <frank@chagford.com>
Subject: Re: Is this unpythonic?
Date: Fri, 8 May 2015 15:12:11 +0200
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"Dave Angel" <davea@davea.name> wrote in message 
news:554CA652.1000607@davea.name...
> On 05/08/2015 06:53 AM, Frank Millman wrote:
>>
>
> It might be appropriate to define the list at top-level, as
>
> EMPTY_LIST=[]
>
> and in your default argument as
>     def x(y, z=EMPTY_LIST):
>
> and with the all-caps, you're thereby promising that nobody will modify 
> that list.
>
> (I'd tend to do the None trick, but I think this alternative would be 
> acceptable)
>

Thanks, Dave, I like that idea.

However, as you can see from my other replies, I have decided to go with the 
flow, and use the None trick.

Frank