The Standard Library has been moved to JSR. See the blog post for details.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.import { ERR_INVALID_ARG_TYPE } from "./internal/errors.ts";import { validateFunction } from "./internal/validators.mjs";import { nextTick } from "./process.ts";
type Subscriber = (message: unknown, name?: string) => void;
export class Channel { _subscribers: Subscriber[]; name: string; constructor(name: string) { this._subscribers = []; this.name = name; }
publish(message: unknown) { for (const subscriber of this._subscribers) { try { subscriber(message, this.name); } catch (err) { nextTick(() => { throw err; }); } } }
subscribe(subscription: Subscriber) { validateFunction(subscription, "subscription");
this._subscribers.push(subscription); }
unsubscribe(subscription: Subscriber) { if (!this._subscribers.includes(subscription)) { return false; }
this._subscribers.splice(this._subscribers.indexOf(subscription), 1);
return true; }
get hasSubscribers() { return this._subscribers.length > 0; }}
const channels: Record<string, Channel> = {};
export function channel(name: string) { if (typeof name !== "string" && typeof name !== "symbol") { throw new ERR_INVALID_ARG_TYPE("channel", ["string", "symbol"], name); }
if (!Object.hasOwn(channels, name)) { channels[name] = new Channel(name); }
return channels[name];}
export function hasSubscribers(name: string) { if (!Object.hasOwn(channels, name)) { return false; }
return channels[name].hasSubscribers;}
export function subscribe(name: string, subscription: Subscriber) { const c = channel(name);
return c.subscribe(subscription);}
export function unsubscribe(name: string, subscription: Subscriber) { const c = channel(name);
return c.unsubscribe(subscription);}
export default { channel, hasSubscribers, subscribe, unsubscribe, Channel,};