include sig ... endval sexp_of_t : t ‑> Base.Sexp.tval create : spool ‑> Async_smtp__.Message.Queue.t ‑> name:string ‑> tval to_message : t ‑> Async_smtp__.Message.t Core.Or_error.t Async.Deferred.tval to_message_with_envelope : t ‑> (Async_smtp__.Message.t * Async_smtp_types.Smtp_envelope.t) Core.Or_error.t Async.Deferred.t