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From: Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject: Re: Fast forward-backward (write-read)
Date: Wed, 24 Oct 2012 01:23:58 -0400
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On Tue, 23 Oct 2012 16:35:40 -0700, emile <emile@fenx.com> declaimed the
following in gmane.comp.python.general:

> On 10/23/2012 04:19 PM, David Hutto wrote:
> > forward =  [line.rstrip('\n') for line in f.readlines()]
> 
> f.readlines() will be big(!) and have overhead... and forward results in 
> something again as big.
>
	Well, since file objects are iterable, could one just drop the
.readlines() ? ( ... line in f )

> > backward =  [line.rstrip('\n') for line in reversed(forward)]
> 
> and defining backward looks to me to require space to build backward and 
> hold reversed(forward)
>
	And since the line-ends have already been stripped from forward,
backward should just be:

	backward = reversed(forward)
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/