You can search for identifiers within the package.
in-package search v0.2.0
val set_chartype : string -> string option
val get_chartype : unit -> string
val is_alpha : char -> bool
val is_space : char -> bool
val is_number : char -> bool
val is_lower : char -> bool
val is_upper : char -> bool
val is_alphanumeric : char -> bool
val is_punctation : char -> bool
val is_printable : char -> bool
val is_graphical : char -> bool
val is_hexadecimal : char -> bool
val to_lower : char -> char
val to_upper : char -> char