I'm not sure if I understand this correctly - but I suspect that all you really need to do is split. eg:

Update: - looks like I obviously didn't even remotely understand what you were after, so just pretend I didn't post the below :)

#!/usr/bin/perl -w
use strict;
use Data::Dumper::Simple;

my $string = "TXXXABCDGXXXCCCDTGYYYCCCYYYCC";

my @wanted = split /XXX|YYY/, $string;

print Dumper(@wanted);
[download]

Gives:

@wanted = (
            'T',
            'ABCDG',
            'CCCDTG',
            'CCC',
            'CC'
          );
[download]

Is that what you were after?

Cheers,
Darren :)