You can search for identifiers within the package.
in-package search v0.2.0
io
Elements.Result
module Public : sig ... end
include module type of struct include Public end
type ('a, 'e) result = ('a, 'e) Public.result =
| Ok of 'a
| Error of 'e
val ok : 'a -> ('a, 'b) result
val error : 'a -> ('b, 'a) result
type ('a, 'e) t = ('a, 'e) result