module type INPUT =Give to this module a way to access libraries, packages, and dependencies between files.sig
..end
val fold_dependencies : (string -> string -> 'a -> 'a) -> 'a -> 'a
val fold_libraries : (string -> string list -> 'a -> 'a) -> 'a -> 'a
val fold_packages : (string -> string list -> 'a -> 'a) -> 'a -> 'a