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From: arn...@skeeve.com (Aharon Robbins)
Newsgroups: comp.lang.awk
Subject: Re: Reading hexadecimal numbers
Date: Wed, 10 Oct 2012 18:04:27 +0000 (UTC)
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References: <201210011523092493@webuse.net> <20121009220128.634@kylheku.com> <k53tak$20b$1@dont-email.me> <20121010095732.587@kylheku.com>
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In article <20121010095732....@kylheku.com>,
Kaz Kylheku  <k...@kylheku.com> wrote:
>One use for assignment might be to set up a configuration area in the program
>where it is customized.
>
>What if the regex is to occur in multiple places? If it's not in a variable,
>it has to be repeated.

This is why, since ~ 1988, awk has allowed the use of string variables
(and constants) where regexp constants are typically used.  Thus

	BEGIN { x = "foo{3,5}(bar)+" }
	...
	$0 ~ x { ... }
	{ ... ; if (match(a, x)) ... }

It's not a 1-for-1 swap, and there are some caveats to be aware of
when doing this, documented in the gawk manual, but this kind of thing
is possible.

Just for the record, while I agree it would have been nice to have /regex/
as first class objects, it wasn't done, and it's too late now.
-- 
Aharon (Arnold) Robbins 			arnold AT skeeve DOT com
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