You can search for identifiers within the package.
in-package search v0.2.0
module L = BatList
val with_in_file : string -> (Stdlib.in_channel -> 'a) -> 'a
val with_out_file : string -> (Stdlib.out_channel -> 'a) -> 'a
val stddev : float list -> float
val lines_of_file : string -> string list
val filter_lines_of_file : string -> (string -> bool) -> string list