You can search for identifiers within the package.
in-package search v0.2.0
type backend
type t
type error = [
| `Msg of string
| `No_data of [ `raw ] Domain_name.t * Dns.Soa.t
| `No_domain of [ `raw ] Domain_name.t * Dns.Soa.t
]
val getrrecord : t -> 'v Dns.Rr_map.rr -> 'a Domain_name.t -> (('v, [> error ]) Stdlib.result, backend) io