Would this work for you? The validation check would be in a subroutine "is_good". 
    my $value = "001003051";
    my $three;
    my $start = 0;

    while ($three = substr $value, $start, 3) {
        ## Do validation check on $three
        break unless is_good($three);

        $start += 3;
    }

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In reply to Re: Parsing a string for sorting by btrott
in thread Parsing a string for sorting by grasshopper

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