val sexp_of_t : ('a -> Ppx_sexp_conv_lib.Sexp.t) -> 'a t -> Ppx_sexp_conv_lib.Sexp.t
val to_type_id : 'a t -> 'a Type_equal.Id.tFor correct behavior of the map,
to_type_idmust return the sameType_equal.Idon different calls on the same input.
Univ_map.Keyval sexp_of_t : ('a -> Ppx_sexp_conv_lib.Sexp.t) -> 'a t -> Ppx_sexp_conv_lib.Sexp.tval to_type_id : 'a t -> 'a Type_equal.Id.tFor correct behavior of the map, to_type_id must return the same Type_equal.Id on different calls on the same input.