@cch137/emitter/index.js

`@cch137/emitter` is a versatile event emitter package designed to work seamlessly in both browser and Node.js environments. It provides a simple yet powerful interface for managing event-driven architecture in your applications.

import { Collection, WeakCollection } from "./group.js";
export default class Emitter {
    listeners = new Collection();
    onces = new WeakCollection();
    on(eventName, listener) {
        this.listeners.group(eventName).push(listener);
        return this;
    }
    once(eventName, listener) {
        const l = this.listeners.group(eventName);
        this.onces.group((l.push(listener), l)).push(listener);
        return this;
    }
    off(eventName, listener) {
        this.listeners.get(eventName)?.deleteOne(listener);
        this.listeners.trim();
        return this;
    }
    emit(eventName, ...args) {
        const l = this.listeners.get(eventName);
        l?.forEach(async (i) => i(...args));
        if (l)
            this.onces.once(l)?.forEach((i) => l.deleteOne(i));
        this.listeners.trim();
        return true;
    }
    clear(eventName, ...args) {
        this.listeners.delete(eventName);
        return this;
    }
}