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From: Ilkka Virta <itvirta@iki.fi>
Newsgroups: gnu.bash.bug
Subject: Re: Incorrect example for `[[` command.
Date: Sat, 21 Sep 2019 01:53:37 +0300
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On 20.9. 21:39, Chet Ramey wrote:

> The portion of the manual before the example explains BASH_REMATCH and
> BASH_REMATCH[0]. It also says "a sequence of characters in the value..."
> when describing the pattern. 

Yeah, though the preceding paragraph contains both the general 
description of the regex match, and the mention of BASH_REMATCH, so the 
BASH_REMATCH angle could be a bit more explicit.

So I'd probably say that the pattern would match e.g. 'xxx aabyyy', or 
'xxxbyyy' and set $BASH_REMATCH to ' aab', or 'b', respectively. And 
then mention that the ^ and $ anchors could be used.

I know the usual regex behavior is to find a match anywhere within the 
value, but since it's exactly the opposite of how regular pattern 
matches work, it's probably worth mentioning in some way.  (Though I do 
think it's better to document things rather explicitly in general.)


-- 
Ilkka Virta / itvirta@iki.fi