Untested: 
foreach my $pattern (@patterns) {
    for (my $i = 0; $i < length($string); $i += 3) {
        push @matches, ${^MATCH}
              if substr($string, $i) =~ /^$pattern/p;
    }
}

[download]
It shouldn't be hard to adapt if you want the offsets (as your original code does). It does capture overlapping matches, although with the given patterns, no overlap is possible.

In reply to Re: Perl Regex Repeating Patterns by JavaFan
in thread Perl Regex Repeating Patterns by Anonymous Monk

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