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From: tchrist@convex.COM (Tom Christiansen)
Newsgroups: comp.lang.perl
Subject: Re: Perl question relating to pattern substitution
Message-ID: <1991Jan05.173102.19622@convex.com>
Date: 5 Jan 91 17:31:02 GMT
References: <1991Jan5.051035.7202@csn.org> <1991Jan05.155212.16460@convex.com>
Sender: usenet@convex.com (news access account)
Reply-To: tchrist@convex.COM (Tom Christiansen)
Organization: CONVEX Software Development, Richardson, TX
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To atob and print out a line, this is substantially faster:

    print pack("C" x ((length)/2),
	grep( ($_ = hex) || 1, unpack ("A2"x((length)/2), $_)));

While these are also interesting:

    print pack('C',hex($1)) while s/^(..)//;

and this:

    for ($len = (length)/2, $i = 0; $i < $len; $i++) {
	print pack('C',hex(substr($_,$i*2,2)));
    } 

although conceptually I still like the semi-original:

    s/(..)/pack("C",hex($1))/eg; 

I begin to think there are nearly unlimited ways to do nearly
*anything* in perl.  Can anybody find some more, preferably
faster?

--tom
--
Tom Christiansen		tchrist@convex.com	convex!tchrist

	"EMACS belongs in <sys/errno.h>: Editor Too Big!" -me