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Re: lowercase letters for binaries

From: Charles Levert
Subject: Re: lowercase letters for binaries
Date: Mon, 7 Nov 2005 16:25:31 -0500
User-agent: Mutt/1.4.1i

* On Monday 2005-11-07 at 21:40:49 +0100, Benno Schulenberg wrote:
> So maybe the 
> following is a better text for 'info grep usage':
> 13. Why is this back-reference failing?
>         echo "ba" | egrep '(a)\1|b\1'
>     This gives no output, because the first alternate '(a)\1' does
>     not match, as there is no "aa" in the input, so the '\1' in the
>     second alternate has nothing to refer back to, meaning it will
>     never match anything.  (The second alternate in this example
>     can only match if the first alternate has matched -- making
>     the second one superfluous.)

I like it.

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