sig
type t =
OpamTypes.package_set * OpamTypes.package_set *
OpamTypes.pin_option OpamPackage.Name.Map.t
val empty : t
val write : OpamTypes.filename -> t -> unit
val read : OpamTypes.filename -> t
val safe_read : OpamTypes.filename -> t
val read_from_channel : in_channel -> t
val write_to_channel : out_channel -> t -> unit
end