You can search for identifiers within the package.
in-package search v0.2.0
type 'a t
val (>>=) : 'a t -> ('a -> 'b t) -> 'b t
val fail : exn -> 'a t
val return : 'a -> 'a t
type handle
val really_read : handle -> int64 -> int -> Cstruct.t t
val really_write : handle -> int64 -> Cstruct.t -> unit t
val really_read_into : handle -> int64 -> Cstruct.t -> Cstruct.t t