declare namespace Opti.Evented {
    class EventEmitter<T extends Record<string, unknown[]>> {
        private _evmap;
        on<K extends string, L extends unknown[]>(ev: K, callback: (...args: L) => void): asserts this is EventEmitter<T & {
            [P in K]: L;
        }>;
        off<K extends keyof T>(ev: K): asserts this is EventEmitter<Omit<T, K>>;
        emit<K extends keyof T>(ev: K, ...args: T[K]): void;
    }
}