export type Parameters<F> = F extends (...args: infer T) => any ? T : never;

export abstract class MessageBus<T> {
  abstract on<E extends keyof T>(topic: E, cb: T[E]): void;
  abstract once<E extends keyof T>(topic: E, cb: T[E]): void;
  abstract emit<E extends keyof T>(topic: E, args?: Parameters<T[E]>): boolean;
  abstract destroy(): void;
}