DispatchedFn
import type { DispatchedFn } from "https://raw.githubusercontent.com/nats-io/nats.deno/v1.28.2/nats-base-client/internal_mod.ts";
DispatcherFn allows for values to be processed after being presented to the iterator. Note that if the ProtocolFilter rejected the value it will not be presented to the DispatchedFn. Any processing should instead have been handled by the ProtocolFilterFn.
type DispatchedFn<T = unknown> = (data: T | null) => void;