You can search for identifiers within the package.
in-package search v0.2.0
frama-c-wp.core
Wp.Cleaning
type usage
val create : unit -> usage
val as_atom : usage -> Lang.F.pred -> unit
val as_type : usage -> Lang.F.pred -> unit
val as_have : usage -> Lang.F.pred -> unit
val as_init : usage -> Lang.F.pred -> unit
val filter_type : usage -> Lang.F.pred -> Lang.F.pred
val filter_pred : usage -> Lang.F.pred -> Lang.F.pred