You can search for identifiers within the package.
in-package search v0.2.0
type ('a, 'b) t
val t_of_sexp : (Sexp.t -> 'a) -> (Sexp.t -> 'b) -> Sexp.t -> ('a, 'b) t
val sexp_of_t : ('a -> Sexp.t) -> ('b -> Sexp.t) -> ('a, 'b) t -> Sexp.t