Emitting events natively.

events.ts

class Emitter<E extends Record<string, new (...args: any[]) => Event>> extends EventTarget {
    constructor(public events: E) {
        super();
    }

    on<T extends keyof E>(event: T, listener: (e: InstanceType<E[T]>) => void) {
        this.addEventListener(event as string, listener as (e: Event) => void);
        return this;
    }

    once<T extends keyof E>(event: T, listener: (e: InstanceType<E[T]>) => void) {
        this.addEventListener(event as string, listener as (e: Event) => void, { once: true });
        return this;
    }

    off<T extends keyof E>(event: T, listener: (e: InstanceType<E[T]>) => void) {
        this.removeEventListener(event as string, listener as (e: Event) => void);
        return this;
    }

    emit<T extends keyof E>(event: T, ...args: ConstructorParameters<E[T]>) {
        this.dispatchEvent(new this.events[event](...args));
        return this;
    }
}