This could be generalized to extract substrings, not just substring initial offsets; also to avoid  $& which just slows everything down. (The many evals might slow things down, though. Oh, well...) (Also tested under 5.8.9.)

c:\@Work\Perl>perl -wMstrict -le
"use Data::Dumper;
 ;;
 $_ = 'abcdfoofrobnicatebardefforspambazghi';
 ;;
 my $re = qr{ (fo.) (.*?) (ba.) }xms;
 ;;
 my %res;
 while (/($re)/g) {
   $res{$1} = [ map eval qq{\$$_}, 2 .. $#- ];
   }
 print Dumper \%res;
"
$VAR1 = {
          'forspambaz' => [
                            'for',
                            'spam',
                            'baz'
                          ],
          'foofrobnicatebar' => [
                                  'foo',
                                  'frobnicate',
                                  'bar'
                                ]
        };
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