Ambiguous range in transliteration operator at test14.pl line 7 (#1) (F) You wrote something like tr/a-z-0// which doesn't mean anything at all. To include a - character in a transliteration, put it either first or last. (In the past, tr/a-z-0// was synonymous with tr/a-y//, which was probably not what you would have expected.) Uncaught exception from user code: Ambiguous range in transliteration operator at test14.pl line 7.