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To: python-list@python.org
From: Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject: Re: Multi-dimensional list initialization
Date: Fri, 09 Nov 2012 14:34:41 -0500
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Xref: csiph.com comp.lang.python:33046

On Fri, 9 Nov 2012 17:07:09 +1100, Chris Angelico <rosuav@gmail.com>
declaimed the following in gmane.comp.python.general:

> On Fri, Nov 9, 2012 at 12:39 PM, Mark Lawrence <breamoreboy@yahoo.co.uk> wrote:
> > On 07/11/2012 01:55, Steven D'Aprano wrote:
> >>
> >>
> >> Who knows? Who cares? Nobody does:
> >>
> >> n -= n
> >>
> >
> > But I've seen this scattered through code:
> >
> > x := x - x - x
> 
> Can you enlighten us as to how this is better than either:
>  x := -x
> or
>  x := 0 - x

	Of course, if one has a language that, for some reason, evaluates
right-to-left (APL, anyone), then

	x := x - x - x

becomes

	x := x - 0

<G>

-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/