You can search for identifiers within the package.
in-package search v0.2.0
top-closure
Top_closure
module type Monad = sig ... end
module type Keys = sig ... end
module type Top_closure = sig ... end
module Make (Keys : Keys) (Monad : Monad) : Top_closure with type key := Keys.elt and type 'a monad := 'a Monad.t