`sig external length : bytes -> int = "%string_length" external get : bytes -> int -> char = "%string_safe_get" external set : bytes -> int -> char -> unit = "%string_safe_set" external create : int -> bytes = "caml_create_string" val make : int -> char -> bytes val init : int -> f:(int -> char) -> bytes val empty : bytes val copy : bytes -> bytes val of_string : string -> bytes val to_string : bytes -> string val sub : bytes -> pos:int -> len:int -> bytes val sub_string : bytes -> int -> int -> string val fill : bytes -> pos:int -> len:int -> char -> unit val blit : src:bytes -> src_pos:int -> dst:bytes -> dst_pos:int -> len:int -> unit val concat : sep:bytes -> bytes list -> bytes val iter : f:(char -> unit) -> bytes -> unit val iteri : f:(int -> char -> unit) -> bytes -> unit val map : f:(char -> char) -> bytes -> bytes val mapi : f:(int -> char -> char) -> bytes -> bytes val trim : bytes -> bytes val escaped : bytes -> bytes val index : bytes -> char -> int val rindex : bytes -> char -> int val index_from : bytes -> int -> char -> int val rindex_from : bytes -> int -> char -> int val contains : bytes -> char -> bool val contains_from : bytes -> int -> char -> bool val rcontains_from : bytes -> int -> char -> bool val uppercase : bytes -> bytes val lowercase : bytes -> bytes val capitalize : bytes -> bytes val uncapitalize : bytes -> bytes type t = bytes val compare : BytesLabels.t -> BytesLabels.t -> int external unsafe_get : bytes -> int -> char = "%string_unsafe_get" external unsafe_set : bytes -> int -> char -> unit = "%string_unsafe_set" external unsafe_blit : src:bytes -> src_pos:int -> dst:bytes -> dst_pos:int -> len:int -> unit = "caml_blit_string" [@@noalloc] external unsafe_fill : bytes -> pos:int -> len:int -> char -> unit = "caml_fill_string" [@@noalloc] val unsafe_to_string : bytes -> string val unsafe_of_string : string -> bytes end`