It works somewhat but I keep getting this repetitive loop when I try it on a larger string. After looking through "mastering regular expressions" by O'Reilly I came up with this:

use strict;
use warnings;

my $string = qq[FGTXYZGTFABCGHABCFGTXYZADXYZGTYABC];
#or try this my $string = qq[FGTXYZABCABC];
$string =~ m/[XYZ]{3}([A-Za-z]{0,21}?)[ABC]{3}?(?{print "matched at [<
+$&>] $-[0]\n" })(?!)/x;

[download]
This seems to work, but I am sort of confused as to how it works !!
Vince

In reply to Re: Re(6): nested pattern matching by vinforget
in thread nested pattern matching by vinforget

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