`sig val iter : f:('a -> unit) -> 'a BatStream.t -> unit val to_string_fmt : fmt:('a -> string, unit, string) Pervasives.format -> 'a BatStream.t -> string val to_string_fun : fn:('a -> string) -> 'a BatStream.t -> string val foldl : f:('a -> 'b -> 'a * bool option) -> init:'a -> 'b BatStream.t -> 'a val foldr : f:('a -> 'b lazy_t -> 'b) -> init:'b -> 'a BatStream.t -> 'b val fold : f:('a -> 'a -> 'a * bool option) -> init:'a BatStream.t -> 'a val filter : f:('a -> bool) -> 'a BatStream.t -> 'a BatStream.t val map : f:('a -> 'b) -> 'a BatStream.t -> 'b BatStream.t val map2 : f:('a -> 'b -> 'c) -> 'a BatStream.t -> 'b BatStream.t -> 'c BatStream.t val scanl : f:('a -> 'b -> 'a) -> 'a -> 'b BatStream.t -> 'a BatStream.t val scan : f:('a -> 'a -> 'a) -> 'a BatStream.t -> 'a BatStream.t val take_while : f:('a -> bool) -> 'a BatStream.t -> 'a BatStream.t val drop_while : f:('a -> bool) -> 'a BatStream.t -> 'a BatStream.t val merge : f:(bool -> 'a -> bool) -> 'a BatStream.t * 'a BatStream.t -> 'a BatStream.t val switch : f:('a -> bool) -> 'a BatStream.t -> 'a BatStream.t * 'a BatStream.t end`