`sig
type t
val empty : unit -> BatSubstring.t
val to_string : BatSubstring.t -> string
val of_string : string -> BatSubstring.t
val make : int -> char -> BatSubstring.t
val create : int -> BatSubstring.t
val equal : BatSubstring.t -> BatSubstring.t -> bool
val of_input : BatIO.input -> BatSubstring.t
val substring : string -> int -> int -> BatSubstring.t
val unsafe_substring : string -> int -> int -> BatSubstring.t
val extract : string -> int -> int option -> BatSubstring.t
val all : string -> BatSubstring.t
val base : BatSubstring.t -> string * int * int
val is_empty : BatSubstring.t -> bool
val getc : BatSubstring.t -> (char * BatSubstring.t) option
val first : BatSubstring.t -> char option
val triml : int -> BatSubstring.t -> BatSubstring.t
val trimr : int -> BatSubstring.t -> BatSubstring.t
val get : BatSubstring.t -> int -> char
val size : BatSubstring.t -> int
val length : BatSubstring.t -> int
val slice : BatSubstring.t -> int -> int option -> BatSubstring.t
val concat : BatSubstring.t list -> string
val explode : BatSubstring.t -> char list
val is_prefix : string -> BatSubstring.t -> bool
val compare : BatSubstring.t -> BatSubstring.t -> int
val index : BatSubstring.t -> char -> int
val index_from : BatSubstring.t -> int -> char -> int
val rindex : BatSubstring.t -> char -> int
val rindex_from : BatSubstring.t -> int -> char -> int
val contains : BatSubstring.t -> char -> bool
val dropl : (char -> bool) -> BatSubstring.t -> BatSubstring.t
val dropr : (char -> bool) -> BatSubstring.t -> BatSubstring.t
val takel : (char -> bool) -> BatSubstring.t -> BatSubstring.t
val taker : (char -> bool) -> BatSubstring.t -> BatSubstring.t
val splitl :
(char -> bool) -> BatSubstring.t -> BatSubstring.t * BatSubstring.t
val splitr :
(char -> bool) -> BatSubstring.t -> BatSubstring.t * BatSubstring.t
val split_at : int -> BatSubstring.t -> BatSubstring.t * BatSubstring.t
val span : BatSubstring.t -> BatSubstring.t -> BatSubstring.t
val translate : (char -> char) -> BatSubstring.t -> string
val tokens : (char -> bool) -> BatSubstring.t -> BatSubstring.t list
val fields : (char -> bool) -> BatSubstring.t -> BatSubstring.t list
val fold_left : ('a -> char -> 'a) -> 'a -> BatSubstring.t -> 'a
val fold_right : (char -> 'a -> 'a) -> BatSubstring.t -> 'a -> 'a
val iter : (char -> unit) -> BatSubstring.t -> unit
val iteri : (int -> char -> unit) -> BatSubstring.t -> unit
val trim : BatSubstring.t -> BatSubstring.t
val split_on_char : char -> BatSubstring.t -> BatSubstring.t list
val split_on_pipe : BatSubstring.t -> BatSubstring.t list
val split_on_dot : BatSubstring.t -> BatSubstring.t list
val split_on_comma : BatSubstring.t -> BatSubstring.t list
val split_on_slash : BatSubstring.t -> BatSubstring.t list
val enum : BatSubstring.t -> char BatEnum.t
val print : 'a BatIO.output -> BatSubstring.t -> unit
end`