1signature UTF8 = 2sig 3 4 exception BadUTF8 of string 5 val getChar : string -> ((string * int) * string) option 6 val lastChar : string -> (string * int) option 7 val size : string -> int 8 val chr : int -> string (* May raise Chr *) 9 val padRight : char -> int -> string -> string 10 val substring : string * int * int -> string 11 12 val translate : (string -> string) -> string -> string 13end 14