class BroadcastChannel implements Sender<TMsg>, Closer, Subscribable<TMsg, TTopic>import { BroadcastChannel } from "https://deno.land/x/async_channels@1.0.0-alpha45/broadcast.ts"; ConstructorsnewBroadcastChannel(topicFn: (val: TMsg) => TTopic, options?)Type ParametersTMsgTTopicPropertiesprotectedfnSubscribers: Map<TopicFn<TTopic>, Set<SendCloser<TMsg>>>protectedreadonlyoptions: BroadcastChannelOptionsprotectedsubscribers: Map<TTopic | symbol, Set<SendCloser<TMsg>>>readonlyisOpenMethodsclose()send(msg: TMsg, abortCtrl?: AbortController): Promise<void>subscribe(topic: TTopic | TopicFn<TTopic>): [Receiver<TMsg>, () => void]