The variable $i was being re-used and overwriting the necessary value that was being passed to a subroutine. Renaming $i to $j fixed it. I also added an extra safety check within parse_letter that would also have prevented this bug.
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
