type ('a, 'b) named
type a
val a : a Typerep.t
type b
val b : b Typerep.t
type t
val typename_of_named : 'a Typerep_lib.Typename.t ‑> 'b Typerep_lib.Typename.t ‑> ('a, 'b) named Typerep_lib.Typename.t
val typename_of_t : t Typerep_lib.Typename.t
val witness : (t, (a, b) named) Typerep_lib.Type_equal.t