You can search for identifiers within the package.
in-package search v0.2.0
directories
Directories.Project_dirs
module App_id : sig ... end
val cache_dir : Fpath.t option
val config_dir : Fpath.t option
val data_dir : Fpath.t option
val data_local_dir : Fpath.t option
val preference_dir : Fpath.t option
val runtime_dir : Fpath.t option
val state_dir : Fpath.t option