Biocaml_unix.Roman_numRoman numerals. Values greater than or equal to 1 are valid roman numerals.
val of_roman : string -> t Core_kernel.Or_error.tParse string as a roman numeral if possible. Case-insensitive.
val of_arabic : int -> t Core_kernel.Or_error.tConvert integer to roman numeral. Return Error if given int is less than 1.
val to_roman : t -> stringString representation of a roman numeral.
val to_arabic : t -> intInteger representation of a roman numeral.